基于功能化石墨烯构建电化学传感器及免疫传感器
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摘要
实验中根据不同的实验需求对石墨烯进行了功能化或改变了石墨烯修饰电极的制备方法,不但改善了石墨烯的分散性,而且赋予了石墨烯某些新的特性。主要研究内容如下：
1.借助氧化石墨烯上的羧基、环氧基和羟基,可以不通过其它连接剂使纳米金附着在石墨烯片层上。实验中以氧化石墨烯和氯金酸为反应物,采用水相共还原法制备了石墨烯／纳米金复合材料。通过功能化解决了石墨烯不易分散、易团聚等问题。与裸电极比石墨烯／纳米金复合材料对肾上腺素具有更高的灵敏度和催化能力。线性范围是5.0×10-8～8.0×10-6mol L-1,在信噪比为3的情况下检测限为7.0×10-9mol L-1。而且该复合材料对其他生物小分子也有较大的响应信号,在分析检测中具有潜在的应用价值。
2.离子液体不但可以作为石墨烯／纳米金复合材料的分散介质,在构建的传感器中还起到增敏作用。将分散于离子液体中的石墨烯／纳米金复合材料修饰到电极表面,将氧化还原媒介体硫堇通过键合作用固定到修饰电极表面,构建了一种无酶型过氧化氢传感器。线性范围是4.0×10"6～2.9×10-3molL-1,检出限为4.3×10-7molL-1(S/N=3)。
3.由于氧化石墨烯中含氧官能团的存在,使得氧化石墨烯片层之间因为电荷斥力的影响能在水中稳定分散,不易发生堆积。实验中,以氧化石墨烯的水溶液为沉积液,用电化学方法将氧化石墨烯还原成石墨烯,并同步沉积到玻碳电极上,制备了电沉积石墨烯修饰电极。茶碱在电沉积石墨烯修饰电极上具有较高的响应信号,线性范围是8.0×10-1检出限为6.0×10-7mol L-1(S/N=3)。
4.聚二烯丙基二甲基胺盐酸盐可以通过π-π键与石墨烯结合,组成阳离子聚电解质功能化的石墨烯。以硫堇为连接剂将纳米金附着在二氧化硅纳米小球上,纳米金不但为抗体提供了活性位点,而且起到信号放大作用。而硫堇既是连接剂,又是氧化还原的媒介体。将功能化的石墨烯修饰在电极表面,利用静电吸附作用将纳米金杂化的小硅球固定在电极上,再利用纳米金与抗体的吸附性有效的将抗体固定在修饰玻碳电极上。修饰电极的大的比表面积和它良好的生物相容性不仅增加了对抗体的固定量而且保持了抗体的生物活性。使得构建的免疫传感器具有较高的灵敏度,且该免疫传感器线性范围宽、重现性好、特异性高。
Different methods have been used to improve the solvency of GR by functionalization or electrodeposition to prepare GR modified electrode. The main contents can be summarized as follows:
1. The gold nanoparticles appear to adhere to GR that act as spacers to inhibit aggregation of GR sheets. The obtained GR/Au nanocomposites modified glassy carbon electrode exhibited high sensitivity in the detection of epinephrine (EP). It has been found that oxidation of EP at this modified electrode occurred at less positive potentials than on bare GCE. The anodic peak current observed were directly proportional to EP concentration between the range of5.0×10--8.0×10mol L-1(LOD=7.0×10-9mol L-1). At the same time, this electrode also showed favorable electrocatalytic activity toward some other small biomolecules (such as dopamine, β-nicotinamide adenine dinucleotide, uric acid et al.), suggesting the potential applications of GR/Au nanocomposites for constructing biosensors.
2. A solution-based method was used to prepare GR/Au nanocomposites via a chemical co-reduction. The obtained GR/Au nanocomposites were easily dispersed homogeneously into N,N-dimethylformamide (DMF) in the presence of ionic liquids (ILs)1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]). First, GR/Au/ILs composites modified electrode (GR/Au/ILs/GCE) was fabricated. Second, thionine (Thi) was chemisorbed onto GR/Au/ILs films through the electrostatic force with the nano-Au. Then the result electrode was applied for the sensitive determination of hydrogen peroxide (H2O2). The results indicated that presence of ILs not only disperse the GR/Au nanocomposites but also increase the sensitivity for H2O2. The sensor displayed a linear range range from4.0×-6to2.9×10-3mol L-1. The detection limit was4.3×10-7mol L-1(S/N=3).
3. A simple and rapid electrochemical method was developed for the determination of theophylline (TP), based on the excellent properties of ED-GO film. The result indicated that ED-GO film modified GCE exhibited efficiently electrocatalytic oxidation for TP with relatively high sensitivity and stability. The electrochemical behavior of TP at ED-GO/GCE was investigated in detail. Under the optimized conditions, the oxidation peak current was proportional to TP concentration in the range of8.0×10-7to6.0×10-5mol L-1with the detection limit of6.0×10-7mol L-1(S/N=3). The proposed method was successfully applied to green tea samples with satisfactory results.
4. The fuctionalized graphene with poly(diallyldimethylammonium chloride)(PDDA-GR) was modifed on the glassy carbon electrode, which can increase the surface area to combine more negtive-charged prepared silica nanoparticles. Nano-gold was coated on silica nanoparticles through thionine linking, which was used to immobilize antibodies. Interlayer thionine was not only a bridging but also an excellent electron mediator. The proposed immunosensor exhibited simple fabrication, good reproducibility and a broad linear range.
1.借助氧化石墨烯上的羧基、环氧基和羟基,可以不通过其它连接剂使纳米金附着在石墨烯片层上。实验中以氧化石墨烯和氯金酸为反应物,采用水相共还原法制备了石墨烯／纳米金复合材料。通过功能化解决了石墨烯不易分散、易团聚等问题。与裸电极比石墨烯／纳米金复合材料对肾上腺素具有更高的灵敏度和催化能力。线性范围是5.0×10-8～8.0×10-6mol L-1,在信噪比为3的情况下检测限为7.0×10-9mol L-1。而且该复合材料对其他生物小分子也有较大的响应信号,在分析检测中具有潜在的应用价值。
2.离子液体不但可以作为石墨烯／纳米金复合材料的分散介质,在构建的传感器中还起到增敏作用。将分散于离子液体中的石墨烯／纳米金复合材料修饰到电极表面,将氧化还原媒介体硫堇通过键合作用固定到修饰电极表面,构建了一种无酶型过氧化氢传感器。线性范围是4.0×10"6～2.9×10-3molL-1,检出限为4.3×10-7molL-1(S/N=3)。
3.由于氧化石墨烯中含氧官能团的存在,使得氧化石墨烯片层之间因为电荷斥力的影响能在水中稳定分散,不易发生堆积。实验中,以氧化石墨烯的水溶液为沉积液,用电化学方法将氧化石墨烯还原成石墨烯,并同步沉积到玻碳电极上,制备了电沉积石墨烯修饰电极。茶碱在电沉积石墨烯修饰电极上具有较高的响应信号,线性范围是8.0×10-1检出限为6.0×10-7mol L-1(S/N=3)。
4.聚二烯丙基二甲基胺盐酸盐可以通过π-π键与石墨烯结合,组成阳离子聚电解质功能化的石墨烯。以硫堇为连接剂将纳米金附着在二氧化硅纳米小球上,纳米金不但为抗体提供了活性位点,而且起到信号放大作用。而硫堇既是连接剂,又是氧化还原的媒介体。将功能化的石墨烯修饰在电极表面,利用静电吸附作用将纳米金杂化的小硅球固定在电极上,再利用纳米金与抗体的吸附性有效的将抗体固定在修饰玻碳电极上。修饰电极的大的比表面积和它良好的生物相容性不仅增加了对抗体的固定量而且保持了抗体的生物活性。使得构建的免疫传感器具有较高的灵敏度,且该免疫传感器线性范围宽、重现性好、特异性高。
Different methods have been used to improve the solvency of GR by functionalization or electrodeposition to prepare GR modified electrode. The main contents can be summarized as follows:
1. The gold nanoparticles appear to adhere to GR that act as spacers to inhibit aggregation of GR sheets. The obtained GR/Au nanocomposites modified glassy carbon electrode exhibited high sensitivity in the detection of epinephrine (EP). It has been found that oxidation of EP at this modified electrode occurred at less positive potentials than on bare GCE. The anodic peak current observed were directly proportional to EP concentration between the range of5.0×10--8.0×10mol L-1(LOD=7.0×10-9mol L-1). At the same time, this electrode also showed favorable electrocatalytic activity toward some other small biomolecules (such as dopamine, β-nicotinamide adenine dinucleotide, uric acid et al.), suggesting the potential applications of GR/Au nanocomposites for constructing biosensors.
2. A solution-based method was used to prepare GR/Au nanocomposites via a chemical co-reduction. The obtained GR/Au nanocomposites were easily dispersed homogeneously into N,N-dimethylformamide (DMF) in the presence of ionic liquids (ILs)1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]). First, GR/Au/ILs composites modified electrode (GR/Au/ILs/GCE) was fabricated. Second, thionine (Thi) was chemisorbed onto GR/Au/ILs films through the electrostatic force with the nano-Au. Then the result electrode was applied for the sensitive determination of hydrogen peroxide (H2O2). The results indicated that presence of ILs not only disperse the GR/Au nanocomposites but also increase the sensitivity for H2O2. The sensor displayed a linear range range from4.0×-6to2.9×10-3mol L-1. The detection limit was4.3×10-7mol L-1(S/N=3).
3. A simple and rapid electrochemical method was developed for the determination of theophylline (TP), based on the excellent properties of ED-GO film. The result indicated that ED-GO film modified GCE exhibited efficiently electrocatalytic oxidation for TP with relatively high sensitivity and stability. The electrochemical behavior of TP at ED-GO/GCE was investigated in detail. Under the optimized conditions, the oxidation peak current was proportional to TP concentration in the range of8.0×10-7to6.0×10-5mol L-1with the detection limit of6.0×10-7mol L-1(S/N=3). The proposed method was successfully applied to green tea samples with satisfactory results.
4. The fuctionalized graphene with poly(diallyldimethylammonium chloride)(PDDA-GR) was modifed on the glassy carbon electrode, which can increase the surface area to combine more negtive-charged prepared silica nanoparticles. Nano-gold was coated on silica nanoparticles through thionine linking, which was used to immobilize antibodies. Interlayer thionine was not only a bridging but also an excellent electron mediator. The proposed immunosensor exhibited simple fabrication, good reproducibility and a broad linear range.
引文
[1]C. N. R. Rao, K. Biswas, K. S. Subrahmanyam, A. Govindaraj, Graphene, the new nanocarbon. J. Mater. Chem.,2009,19,2457-2469.
[2]C. G. Lee, X. D. Wei, J. W. Kysar, J. Hone, Measurement of the elastic properties and intrinsic strength of monolayer graphene. Science,2008,321 (5887),385-388.
[3]A. A. Balandin, S. Ghosh, W. Z. Bao, I. Calizo, D. Teweldebrhan, F. Miao, C. N. Lau, Superior thermal conductivity of single-layer graphene. Nano Letters.2008,8 (3),902-907.
[4]Z. H. Chen, Y. M. Lin, M. J. Rooks, P. Avouris, Graphene nano-ribbon electronics. Physica E: Low-dimensional systems and nanostructures,2007,40 (2),228-232.
[5]J. R. Dahn, T. Zheng, Y. H. Liu, J. S. Xue, Mechanisms for lithium insertion in carbonaceous materials. Science,1995,270 (5236),590-593.
[6]E. J. Yoo, J. Kim, E. Hosono, H. S. Zhou, T. Kudo, I. Honma, Large reversible Li storage of graphene nanosheet families for use in rechargeable lithium ion batteries. Nano Lett.,2008,8 (8), 2277-2282.
[7]K. S. Subrahmanyam, S. R. C. Vivekchand, A. Govindarai, C. N. R. Rao, A study of graphene prepared by different methods:characterization, properties and solubilization. J. Mater. Chem., 2008,18,1517-1523.
[8]K. S. Novoselov, A. K. Geim, S. V. Morozov et.al. Electric field effect in atomically thin carbon films. Science,2004,306 (5696),666-669.
[9]D. A. C. Brownson, C. E. Banks, Graphene electrochemistry:an overview of potential applications. Analyst.,2010,135,2768-2778.
[10]M. Pumera, Electrochemistry of graphene:new horizons for sensing and energy storage. The Chemical Record,2009,9 (4),211-223.
[11]D. K. Kampouris, C. E. Banks, Exploring the physicoelectrochemical properties of graphene. Chem. Commun.,2010,46,8986-8988.
[12]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature.,2007,446,60-63.
[13]A. K. Geim, K. S. Novoselov, The rise of graphene. Nature Materials.,2007,6,183-191.
[14]K. S. Kim, Y. Zhao, H. Jang, S. Y. Lee, J. M. Kim, K. S. Kim, J. H. Ahn, P. Kim, J. Y. Choi, B. H. Hong, Large-scale pattern growth of graphene films for stretchable transparent electrodes. Nature,2009,457,706-710.
[15]A. Dato, V. Radmilovic, Z. Lee, J. Phillips, M. Frenklach, Substrate-free gas-phase synthesis of graphene sheets. Nano Lett.,2008,8 (7),2012-2016.
[16]V. Borovikov, A. Zangwill. Step-edge instability during epitaxial growth of graphene from SiC (0001). Phys. Rev. B.,2009,80 (12):121406-121409.
[17]W. A. Heer, C. Berger, X. S. Wu, P. N. First, E. H. Conrad, X. B. Li, T. B. Li, M. Sprinkle, J. Hass, M. L. Sadowski, M. Potemski, G. Martinez, Epitaxial graphene. Solid State Commun.,2007, 143 (1-2):92-100.
[18]M. Sprinkle, P. Soukiassian, W. A. Heer, C. Berger, E. H. Conrad, Epitaxial graphene:the material for graphene electronics. Phys. Status Solidi (RRL)-Rapid Research Letters.,2009,3(6): A91-A94.
[19]J. B. Hannon, R. M. Tromp, Pit formation during graphene synthesis on SiC (0001):In situ electron microscopy. Phys. Rev. B.,2008,77(24):241404-241407.
[20]H. J. Shin, K. K. Kim, A. Benayad, S. M. Yoon, H. K. Park, I. S. Jung, M. H. Jin, H. Jeong, J. M. Kim, J. Y. Choi, Y. H. Lee, Efficient reduction of graphite oxide by sodium borohydride and its effect on electrical conductance. Adv Funct Mater.,2009,19 (12),1987-1992
[21]V. C. Tung, M. J. Allen, Y. Yang, R. B. Kaner, High-throughput solution processing of large-scale graphene. Nature Nanotechnology,2009,4(1),25-29
[22]M. Zhou, Y. L. Wang, Y. M. Zhai, J. F. Zhai, W. Ren, F. Wang, S. J. Dong, Controlled synthesis of large-area and patterned electrochemically reduced graphene oxide films. Chem. Eur. J.,2009,15 (25),6116-6120
[23]P. Steurer, R. Wissert, R. Thomann, R. Mulhaupt, Functionalized graphenes and thermoplastic nanocomposites based upon expanded graphite oxide. Macromol. Rapid Commun., 2009,30(4-5),316-327.
[24]H. C. Schniepp, J. L. Li, M. J. McAllister, H. Sai, M. Herrera-Alonso, D. H. Adamson, R. K. Prud'homme, R. Car, D. A. Saville, I. A. Aksay, Functionalized single graphene sheets derived from splitting graphite oxide. J. Phys. Chem. B,2006,110 (17),8535-8539.
[25]M. J. McAllister, J. L. Li, D. H. Adamson, H. C. Schniepp, A. A. Abdala, J. Liu, M. Herrera-Alonso, D. L. Milius, R. Car, R. K. Prud'homme, I. A. Aksay, Single sheet functionalized graphene by oxidation and thermal expansion of graphite. Chem. Mater.,2007,19 (18), 4396-4404.
[26]G. Williams, B. Seger, P. V. Kamat, TiO2-graphene nanocomposites. UV-assisted photocatalytic reduction of graphene oxide. Nano.,2008,2 (7),1487-1491.
[27]L. J. Cote, R. Cruz-Silva, J. X. Huang, Flash reduction and patterning of graphite oxide and its polymer composite. J. Am. Chem. Soc.,2009,131 (31),11027-11032.
[28]K. S. Subrahmanyam, L. S. Panchakarla, A. Govindaraj, C. N. R. Rao, Simple method of preparing graphene flakes by an Arc-Discharge method. J. Phys. Chem. C,2009,113 (11), 4257-4259.
[29]H. L. Qian, F. Negri, C. R. Wang, Z. H. Wang, Fully conjugated tri(perylene bisimides):an approach to the construction of n-type graphene nanoribbons. J. Am. Chem. Soc.,2008,130 (52), 17970-17976.
[30]C. E. Hamilton, J. R. Lomeda, Z. Z Sun, J. M. Tour, A. R. Barron, High-yield organic dispersions of unfunctionalized graphene. Nano Lett.,2009,9 (10),3460-3462.
[31]L. Y. Jiao, L. Zhang, X. R. Wang, G. Diankov, H. J. Dai, Narrow graphene nanoribbons from carbon nanotubes. Nature,2009,458,877-880.
[32]W. X. Zhang, J. C. Cui, C. A. Tao, Y. G. Wu, Z. P. Li, L. Ma, Y. Q. Wen, G. T. Li, A strategy for producing pure single-layer graphene sheets based on a confined self-assembly approach. Angewandte Chemie.,2009,121 (32):5978-5982.
[33]D. W. Boukhvalov, M. I. Katsnelson, Chemical functionalization of graphene. J. Phys.: Condens Matter,2009,21 (34) 344205-344216.
[34]H. Y. He, T. Riedl, A. Lerf, J. Klinowski, Solid-state NMR studies of the structure of graphite oxide. J. Phys. Chem.,1996,100 (51),19954-19958.
[35]H. Y. He, J. Klinowski, M. Forster, A. Lerf, A new structural model for graphite oxide. Chem. Phys. Lett.,1998,287 (1-2),53-56.
[36]A. Lerf, H. Y. He, M. Forster, J. Klinowski, Structure of graphite oxide revisited. J. Phys. Chem. B,1998,102 (23),4477-4482.
[37]W. W. Cai, R. D. Piner, F. J. Stadermann, S. J. Park, M. A. Shaibat, Y. Ishii, D. X. Yang, A. Velamakanni, S. J. An, M. Stoller, J. An, D. M. Chen, R. S. Ruoff, Synthesis and solid-state NMR structural characterization of 13C-labeled graphite oxide. Science,2008,321 (5897),1815-1817.
[38]S. Stankovich, R. D. Piner, X. Q. Chen, N. Q. Wu, S. T. Nguyen, R. S. Ruoff, Stable aqueous dispersions of graphitic nanoplatelets via the reduction of exfoliated graphite oxide in the presence of poly(sodium 4-styrenesulfonate). J. Mater. Chem.,2006,16,155-158
[39]Y. X. Xu, H. Bai, G. W. Lu, C. Li, G. Q. Shi. Flexible graphene films via the filtration of water-soluble noncovalent functionalized graphene sheets. J. Am. Chem. Soc.,2008,130 (18) 5856-5857.
[40]W. J. Hong, Y. X. Xu, G. W. Lu, C. Li, G. Q. Shi. Transparent graphene/PEDOT-PSS composite films as counter electrodes of dye-sensitized solar cells. Electrochem Commun.,2008, 10(10),1555-1558.
[41]C. Valles, C. Drummond, H. Saadaoui, C. A. Furtado, M. S. He, O. Roubeau, L. Ortolani, M. Monthioux, A. Penicaud. Solutions of negatively charged graphene sheets and ribbons. J. Am. Chem. Soc.,2008,130 (47),15802-15804.
[42]D. Li, M. B. Muller, S. Gilje, R. B. Kaner, G. G. Wallace. Processable aqueous dispersions of graphene nanosheets. Nat Nanotechnol.,2008,3,101-105.
[43]Y. Y. Liang, D. Q. Wu, X. L. Feng, K. Mullen, Dispersion of graphene sheets in organic solvent supported by ionic interactions. Adv Mater.,2009,21 (17),1679-1683.
[44]X. Y. Yang, Z. Y. Zhang, Z. F. Liu, Y. F. Ma, Y. Huang, Y. S. Chen. High-efficiency loading and controlled release of doxorubicin hydrochloride on graphene oxide. J. Phys. Chem. C,2008, 112(45),17554-17558.
[45]A. J. Patil, J. L. Vickery, T. B. Scott, S. Mann, Aqueous stabilization and self-assembly of graphene sheets into layered bio-nanocomposites using DNA. Adv. Mater.2009,21 (31), 3159-3164.
[46]S. Stankovich, R. D. Piner, S. T. Nguyen, R. S. Ruoff. Synthesis and exfoliation of isocyanate-treated graphene oxide nanoplatelets. Carbon,2006,44 (15),3342-3347.
[47]S. Niyogi, E. Bekyarova, M. E. Itkis, J. L. McWilliams, M. A. Hamon, R. C. Haddon. Solution properties of graphite and graphene. J. Am. Chem. Soc.,2006,128 (24),7720-7721.
[48]S. F. Hou, M. L. Kasner, S. J. Su, K. Patel, R. Cuellari. Highly sensitive and selective dopamine biosensor fabricated with silanized graphene. J. Phys. Chem. C,2010,114 (35), 14915-14921.
[49]J. F. Shen, Y. Z. Hu, C. Li, C. Qin, M. X. Ye. Synthesis of amphiphilic graphene nanoplatelets. Small,2009,5 (1),82-85.
[50]X. Y. Yang, X. Y. Zhang, Y. F. Ma, Y. Huang, Y. S. Wang, Y. S. Chen, Superparamagnetic graphene oxide-Fe3O4 nanoparticles hybrid for controlled targeted drug carriers. J. Mater. Chem., 2009,19,2710-2714.
[51]Y. X. Fang, S. J. Guo, C. Z. Zhu, Y. M. Zhai, E. K. Wang. Self-assembly of cationic polyelectrolyte-functionalized graphene nanosheets and gold nanoparticles:a two-dimensional heterostructure for hydrogen peroxide sensing. Langmuir.2010,26 (13),11277-11282.
[52]W. Chen, S. Chen, D. C. Qi, X. Y. Gao, A. T. S. Wee, Surface transfer p-type doping of epitaxial graphene. J. Am. Chem. Soc.,2007,129 (34),10418-10422.
[53]D. C. Wei, Y. Q. Liu, Y. Wang, H. L. Zhang, L. P. Huang, G. Yu, Synthesis of n-doped graphene by chemical vapor deposition and its electrical properties. Nano Lett.,2009,9 (5), 1752-1758.
[54]X. L. Li, H. L. Wang, J. T. Robinson, H. Sanchez, G. Diankov, H. J. Dai, Simultaneous nitrogen doping and reduction of graphene oxide. J. Am. Chem. Soc.,2009,131 (43), 15939-15944.
[55]K. S. Subrahmanyam, L. S. Panchakarla, A. Govindaraj, C. N. R. Rao, Simple method of preparing graphene flakes by an Arc-discharge method. J. Phys. Chem. C,2009,113 (11), 4257-4259.
[56]N. Li, Z. Y. Wang, K. K. Zhao, Z. J. Shi, Z. N. Gu, S. K. Xu, Large scale synthesis of N-doped multi-layered graphene sheets by simple arc-discharge method. Carbon,2010,48 (1), 255-259.
[57]S. B. Yang, G. L. Cui, S. P. Pang, Q. Cao, U. Kolb, X. L. Feng, J. Maier, K. Mullen, Fabrication of cobalt and cobalt oxide/graphene composites:towards high-performance anode materials for lithium ion batteries. Chem. Sus. Chem.,2010,3 (2),236-239.
[58]G. X. Wang, X. P. Shen, J. Yao, J. Park, Graphene nanosheets for enhanced lithium storage in lithium ion batteries. Carbon.2009,47 (8),2049-2053.
[59]W. Lv, D. M. Tang, Y. B. He, C. H. You, Z. Q. Shi, X. C. Chen, C. M. Chen, P. X. Hou, C. Liu, Q. H. Yang, Low-temperature exfoliated graphenes:vacuum-promoted exfoliation and electrochemical energy storage. ACS Nano,2009,3 (11),3730-3736.
[60]Y. Chen, X. Zhang, P. Yu, Y. W. Ma, Electrophoretic deposition of graphene nanosheets on nickel foams for electrochemical capacitors. Journal of Power Sources,2010,195 (9),3031-3035.
[61]Z. Liu, J. T. Robinson, X. M. Sun, H. J. Dai, PEGylated nanographene oxide for delivery of water-insoluble cancer drugs. J. Am. Chem. Soc.,2008,130 (33):10876-10877.
[62]X. Y. Yang, X. Y. Zhang, Z. F. Liu, Y. F. Ma, Y. Huang, Y. S. Chen, High-efficiency loading and controlled release of doxorubicin hydrochloride on graphene oxide. J. Phys. Chem. C.,2008, 112(45),17554-17558.
[63]P. Ramesh, S. Bhagyalakshmi, S. Sampath, Preparation and physicochemical and electrochemical characterization of exfoliated graphite oxide. J. Colloid Interface Sci.,2004,274 (1),95-102.
[64]F. Schedin, A. K. Geim, S. V. Morozov, E. W. Hill, P. Blake, M. I. Katsnelson, K. S. Novoselov, Detection of individual gas molecules adsorbed on graphene. Nat. Mater.,2007,6, 652-655.
[1]W. R. Yang, K. R. Ratinac, S. P. Ringer, P. Thordarson, J. J. Gooding, F. Braet, Carbon nanomaterials in biosensors:should you use nanotubes or graphene. Angew. Chem. Int. Ed.,2010, 49 (12),2114-2138.
[2]A. K. Geim, K. S. Novoselov, The rise of graphene. Nat. Mater.,2007,6,183-191.
[3]M. Pumera, Electrochemistry of graphene:new horizons for sensing and energy storage. Chem. Rec.,2009,9 (4),211-223.
[4]M. H. Liang, L. J. Zhi, Graphene-based electrode materials for rechargeable lithium batteries. J. Mater. Chem.,2009,19,5871-5878.
[5]Y. Y. Shao, J. Wang, H. Wu, J. Liu, I. A. Aksay, Y. H. Lin, Graphene based electrochemical sensors and biosensors:a review. Electroanal.,2010,22 (10),1027-1036.
[6]Z. J. Wang, X. Z. Zhou, J. Zhang, F. Boey, H. Zhang, Direct electrochemical reduction of single-layer graphene oxide and subsequent functionalization with glucose oxidase. J. Phys. Chem. C,2009,113 (32) 14071-14075.
[7]Y. Wang, Y. M. Li, L. H. Tang, J. Lu, J. H. Li, Application of graphene-modified electrode for selective detection of dopamine. Electrochem. Commun.,2009,11 (4) 889-892.
[8]C. Wang, L. Zhang, Z. H. Guo, J. G. Xu, H. Y. Wang, K. F. Zhai, X. Zhuo, A novel hydrazine electrochemical sensor based on the high specifiec area graphene. Microchim. Acta,2010,169 (1-2),1-6.
[9]C. S. Shan, H. F. Yang, D. X. Han, Q. X. Zhang, A. Ivaska, L. Niu, Water-soluble graphene covalently functionalized by biocompatible poly-L-lysine. Langmuir,2009,25 (20),12030-12033.
[10]D. Li, M. B. Miiller, S. Gilje, R. B. Kaner, G. G. Wallace, Processable aqueous dispersions of graphene nanosheets. Nat. Nanotechnol.,2008,3,101-105.
[11]Y. C. Si, E. T. Samulski, Synthesis of water soluble graphene. Nano Lett.,2008,8 (6), 1679-1682.
[12]Y. Y. Liang, D. Q. Wu, X. L. Feng, K. Mullen, Dispersion of graphene sheets in organic solvent supported by ionic interactions. Adv. Mater.,2009,21 (17),1679-1683.
[13]S. Stankovich, R. D. Piner, X. Q. Chen, N. Q. Wu, S. T. Nguyen, R. S. Ruoff, Stable aqueous dispersions of graphitic nanoplatelets via the reduction of exfoliated graphite oxide in the presence of poly(sodium 4-styrenesulfonate). J. Mater. Chem.,2006,16,155-158.
[14]X. B. Fan, W. C. Peng, Y. Li, X. Y. Li, S. L. Wang, G. L. Zhang, F. B. Zhang, Deoxygenation of exfoliated graphite oxide under alkaline conditions:a green route to graphene preparation. Adv. Mater.,2008,20 (23),4490-4493.
[15]S. Stankovich, D. A. Dikin, G. H. B. Dommett, K. M. Kohlhaas, E. J. Zimney, E. A. Stach, R. D. Piner, S. T. Nguyen, R. S. Ruoff, Graphene-based composite materials. Nature,2006,442, 282-286.
[16]A. P. Yu, P. Ramesh, M. E. Itkis, E. Bekyarova, R. C. Haddon, Graphite nanoplatelet-epoxy composite thermal interface materials. J. Phys. Chem. C,2007,111 (21),7565-7569.
[17]Y. C. Si, E. T. Samulski, Exfoliated graphene separated by platinum nanoparticles. Chem. Mater.,2008,20 (21),6792-6797.
[18]R. Muszynski, B. Seger, P. V. Kamat, Decorating graphene sheets with gold nanoparticles. J. Phys. Chem. C,2008,112 (14),5263-5266.
[19]C. Xu, X. Wang, J. W. Zhu, Graphene-metal particle nanocomposites. J. Phys. Chem. C, 2008,112(50),19841-19845.
[20]C. M. Shen, C. Hui, T. Z. Yang, C. W. Xiao, J. F. Tian, L. H. Bao, S. T. Chen, H. Ding, H. J. Gao, Monodisperse noble-metal nanoparticles and their surface enhanced raman scattering properties. Chem. Mater.,2008,20 (22),6939-6944.
[21]Y. X. Fang, S. J. Guo, C. Z. Zhu, Y. M. Zhai, E. K. Wang, Self-assembly of cationic polyelectrolyte-funcionalized graphene nanosheets and gold nanoparticles:a two-dimensional heterostructure for hydrogen peroxide sensing. Langmuir,2010,26 (13),11277-11282.
[22]F. Liu, J. Y. Choi, T. S. Seo, DNA mediated water-dispersible graphene fabrication and gold nanoparticle-graphene hybrid. Chem. Commun.,2010,46,2844-2846.
[23]W. J. Hong, H. Bai, Y. X. Xu, Z. Y. Yao, Z. Z. Gu, G. Q. Shi, Preparation of gold nanoparticle/graphene composites with controlled weight contents and their application in biosensors. J. Phys. Chem. C,2010,114 (4),1822-1826.
[24]J. B. Liu, S. H. Fu, B. Yuan, Y. L. Li, Z. X. Deng, Toward a universal "adhesive nanosheet" for the assembly of multiple nanoparticles based on a protein-induced reduction/decoration of graphene oxide. J. Am. Chem. Soc.,2010,132 (21),7279-7281.
[25]Y. K. Kim, H. K. Na, D. H. Min, Influence of surface functionalization on the growth of gold nanostructures on graphene thin films. Langmuir,2010,26 (16) 13065-13070.
[26]G. Goncalves, P. A. A. P. Marques, C. M. Granadeiro, H. I. S. Nogueira, M. K. Singh, J. Gracio, Surface modification of graphene nanosheets with gold nanoparticles:the role of oxygen moieties at graphene surface on gold nucleation and growth. Chem. Mater.,2009,21 (20), 4796-4802.
[27]B. S. Kong, J. X. Geng, H. T. Jung, Layer-by-layer assembly of graphene and gold nanoparticles by vacuum filtration and spontaneous reduction of gold ions. Chem. Commun.,2009, 16,2174-2176.
[28]W. A. Banks, Enhanced leptin transport across the blood-brain barrier by al-adrenergic agents. Brain Res.,2001,899 (1-2),209-217.
[29]J. O. Schenk, E. Miller, R. N. Adams, Electrochemical techniques for the study of brain chemistry. J. Chem. Educ.,1983,60 (4) 311-315.
[30]Y. Hasebe, T. Hirano, S. Uchiyama, Determination of catecholamines and uric acid in biological fluids without pretreatment, using chemically amplified biosensors. Sens. Actuators, B, 1995,24 (1-3),94-97.
[31]T. Luczak, Comparison of electrochemical oxidation of epinephrine in the presence of interfering ascorbic and uric acids on gold electrodes modified with S-functionalized compounds and gold nanoparticles. Electrochim. Acta,2009,54 (24) 5863-5870.
[32]A. Sucheta, J. Rusling, Effect of background charge on estimating diffusion coefficients by chronocoulometry at glassy carbon electrodes. Electroanal.,1991,3 (8) 735-739.
[33]X.Z. Wu, L.J. Mu, W.Z. Zhang, Impedance of the electrochemical oxidation of epinephrine on a glassy carbon electrode. J. Electroanal. Chem.,1993,352 (1-2),295-300.
[34]E. L. Ciolkowski, K. M. Maness, P. S. Cahill, R. M. Wightman, D. H. Evans, B. Fosset, C. Amatore, Disproportionation during electrooxidation of catecholamines at carbon-fiber microelectrodes. Anal. Chem.,1994,66 (21) 3611-3617.
[35]M. D. Hawley, S. V. Tatawawadi, S. Piekarski, R. N. Adams, Electrochemical studies of the oxidation pathways of catecholamines. J. Am. Chem. Soc.,1967,89 (2) 447-450.
[36]H. S. Wang, D. Q. Huang, R. M. Liu, Study on the electrochemical behavior of epinephrine at a poly(3-methylthiophene)-modified glassy carbon electrode. J. Electroanal. Chem.,2004,570 (1) 83-90.
[37]H. M. Zhang, X. L. Zhou, R. T. Hui, N. Q. Li, D. P. Liu, Studies of the electrochemical behavior of epinephrine at a homocysteine self-assembled electrode. Talanta,2002,56 (6), 1081-1088.
[38]M. Zhu, X. M. Huang, J. Li, H. X. Shen, Peroxidase-based spectrophotometric methods for the determination of ascorbic acid, norepinephrine, epinephrine, dopamine and levodopa. Anal. Chim. Acta,1997,357 (3),261-267.
[39]K. C. Grabar, R. Griffith Freeman, M. B. Hommer, M. J. Natan, Preparation and characterization of Au colloid monolayers. Anal. Chem.,1995,67 (4) 735-743.
[40]R. J. Bowling, R. T. Packard, R. L. McCreery, Activation of highly ordered pyrolytic graphite for heterogeneous electron transfer:relationship between electrochemical performance and carbon microstructure. J. Am. Chem. Soc.,1989,111 (4),1217-1223.
[41]S. Stankovich, D. A. Dikin, R. D. Piner, K. A. Kohlhass, A. Kleinhammes, Y. Y. Jia, Y. Wu, S. T. Nguyen, R. S. Ruoff, Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide. Carbon,2007,45 (7),1558-1565.
[42]K. N. Kudin, B. Ozbas, H. C. Schniepp, R. K. Prud'homme, I. A. Aksay, R. Car, Raman spectra of graphite oxide and functionalized graphene sheets. Nano Lett.,2008,8 (1) 36-41.
[43]N. D. Mermin, Crystalline order in two dimensions. Phys. Rev.,1968,176 (1),250-254.
[44]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature,2007,446,60-63.
[45]L. Han, X. L. Zhang, Simultaneous voltammetric determination of dihydroxybenzene isomers by nanogold modified electrode. Electroanalysis,2009,21 (2),124-129.
[46]T. Komura, G. Y. Niu, T. Yamaguchi, M. Asano, A. Matsuda, Coupled electron-proton transport in electropolymerized methylene blue and the influences of its protonation level on the rate of electron exchange with β-nicotinamide adenine dinucleotide. Electroanal.,2004,16 (21), 1791-1800.
[47]U. Yogeswaran, S. Thiagarajan, S. M. Chen, Pinecone shape hydroxypropyl-β-cyclodextrin on a film of multi-walled carbon nanotubes coated with gold particles for the simultaneous determination of tyrosine, guanine, adenine and thymine. Carbon,2007,45(14),2783-2796.
[1]T. Seyller, A. Bostwick, K. V. Emtsev, K. Horn, L. Ley, J. L. McChesney, T. Ohta, J. D. Riley, E. Rotenberg, F. Speck, Epitaxial graphene:a new material. Phys. Stat. Sol. B,2008,245 (7), 1436-1446.
[2]C. N. R. Rao, A. K. Sood, K. S. Subrahmanyam, A. Govindaraj, Graphene:The new two-dimensional nanomaterial. Angew. Chem. Int. Ed.,2009,48 (42),7752-7777.
[3]L. H. Tang, Y. Wang, Y. M. Li, H. B. Feng, J. Lu, J. H. Li, Preparation, structure and electrochemical properties of reduced graphene sheet films. Adv. Funct. Mater.,2009,19 (17), 2782-2789.
[4]C. S. Shan, H. F. Yang, J. F. Song, D. X. Han, A. Ivaska, L. Niu, Direct electrochemistry of glucose oxidase and biosensing for glucose based on graphene. Anal. Chem.,2009,81 (6), 2378-2382.
[5]H. Q. Chen, M. B. Miiller, K. J. Gilmore, G. G. Wallace, D. Li, Mechanically strong, electrically conductive, and biocompatible graphene paper. Adv. Mater.,2008,20 (18), 3557-3561.
[6]Y. Wang, Y. M. Li, L. H. Tang, J. Lu, J. H. Li, Application of graphene-modified electrode for selective detection of dopamine. Electrochem. Commun.,2009,11 (4),889-892.
[7]F. H. Li, J. Chai, H. F. Yang, D. X. Han, L. Niu, Synthesis of Pt/ionic liquid/graphene nanocomposite and its simultaneous determination of ascorbic acid and dopamine.2010,81 (3), 1063-1068.
[8]H. K. He, C. Gao, Graphene nanosheets decorated with Pd, Pt, Au, and Ag nanoparticles: synthesis, characterization and catalysis applications. Science China Chemistry,2011,54 (2), 397-404.
[9]Y. Chen, Y. Li, D. Sun, D. B. Tian, J. R. Zhang, J. J. Zhu, Fabrication of gold nanoparticles on bilayer graphene for glucose electrochemical biosensing. J. Mater. Chem.,2011,21,7604-7611.
[10]F. Liu, J. Y. Choi, T. S. Seo, DNA mediated water-dispersible graphene fabrication and gold nanoparticle-graphene hybrid. Chem. Commun.,2010,46,2844-2846.
[11]T. A. Pham, B. C. Choi, K. T. Lim, Y. T. Jeong, A simple approach for immobilization of gold nanoparticles on graphene oxide sheets by covalent bonding. Appl. Surf. Sci.,257 (8), 3350-3357.
[12]J. B. Liu, S. H. Fu, B. Yuan, Y. L. Li, Z. X. Deng, Toward a universal "adhesive nanosheet" for the assembly of multiple nanoparticles based on a protein-induced reduction/decoration of graphene oxide. J. Am. Chem. Soc.,2010,132 (21),7279-7281.
[13]G. Goncalves, P. A. A. P. Marques, C. M. Granadeiro, H. I. S. Nogueira, M. K. Singh, J. Gracio, Surface modification of graphene nanosheets with gold nanoparticles:the role of oxygen moieties at graphene surface on gold micleation and growth. Chem. Mater.,2009,21 (20), 4796-4802.
[14]B. S. Kong, J. X. Geng, H. T. Jung, Layer-by-layer assembly of graphene and gold nanoparticles by vacuum filtration and spontaneous reduction of gold ions. Chem. Commun.,2009, 16,2174-2176.
[15]X. S. Zhou, T. B. Wu, K. L. Ding, B. J. Hu, M. Q. Hou, B. X. Han, Dispersion of graphene sheets in ionic liquid [bmim][PF6] stabilized by an ionic liquid polymer. Chem. Commun.,2010, 46,386-388.
[16]H. Shobukawa, H. Tokuda, M. A. B. H. Susan, M. Watanabe, Ion transport properties of lithium ionic liquids and their ion gels. Electrochim. Acta,2005,50 (19),3872-3877.
[17]P. A. Z. Suarez, V. M. Selbach, J. E. L. Dullius, S. Einloft, C. M. S. Piatnicki, D. S. Azambuja, R. F. Souza, J. Dupont, Enlarged electrochemical window in dialkyl-imidazolium cation based room-temperature air and water-stable molten salts. Electrochim. Acta,1997,42 (16),2533-2535.
[18]H. Shobukawa, H. Tokuda, S. I. Tabata, M. Watanabe, Preparation and transport properties of novel lithium ionic liquids. Electrochim. Acta,2004,50 (2-3),305-309.
[19]T. Fujimoto, M. M. Matsushita, H. Yoshikawa, K. Awaga, Electrochemical and electrochromic properties of octathio circulene thin films in ionic liquids. J. Am. Chem. Soc., 2008,130 (47),15790-15791.
[20]N. Liu, F. Luo, H. X. Wu, Y. H. Liu, C. Zhang, J. Chen, One-step ionic-liquid-assisted electrochemical synthesis of ionic-liquidfunctionalized graphene sheets directly from graphite. Adv. Funct. Mater.,2008,18 (10),1518-1525.
[21]X. B. Lu, Q. Zhang, L. Zhang, J. H. Li, Direct electron transfer of horseradish peroxidase and its biosensor based on chitosan and room temperature ionic liquid. Electrochem. Commun.,2006, 8 (5),874-878.
[22]N. Maleki, A. Safavi, F. Tajabadi, High-performance carbon composite electrode based on an ionic liquid as a binder. Anal. Chem.,2006,78 (11),3820-3826.
[23]W. Sun, D. D. Wang, R. F. Gao, K. Jiao, Direct electrochemistry and electrocatalysis of hemoglobin in sodium alginate film on a [BMIM][PF6] modified carbon paste electrode. Electrochem. Commun.,2007,9 (5),1159-1164.
[24]D. Wei and A. Ivaska, Applications of ionic liquids in electrochemical sensors. Anal. Chim. Acta,2008,607 (2),126-135.
[25]J. Kulys, L. Z. Wang, A. Maksimoviene, L-Lactate oxidase electrode based on methylene green and carbon paste. Anal. Chim. Acta,1993,274 (1),53-58.
[26]K. Yamamoto, T. Ohgaru, M. Torimura, H. Kinoshita, K. Kano, T. Ikeda, Highly-sensitive flow injection determination of hydrogen peroxide with a peroxidase-immobilized electrode and its application to clinical chemistry. Anal. Chim. Acta,2000,406 (2),201-207.
[27]沈友,柴素芬.碘-四氯化碳萃取光度法间接测定食品中的痕量过氧化氢。光谱实验室,2003,20(4),636-638。
[28]S. Sakura, Electrochemiluminescence of hydrogen peroxide-luminol at a carbon electrode. Anal. Chim. Acta,1992,262 (1),49-57.
[29]Q. Y. Chen, D. H. Li, Q. Z. Zhu, H. Zheng, J. G. Xu, Application of iron-tetrasulfonatophthalocyanine as a new mimetic peroxidase in the determination of hydrogen peroxide with p-hydroxyphenylpropionic acid as a substrate. Anal. Chim. Acta,1999,381 (2-3), 175-182.
[30]P. X. Yuan, Y. Zhuo, Y. Q. Chai, H. X. Ju, Dendritic silver/silicon dioxide nanocomposite modified electrodes for electrochemical sensing of hydrogen peroxide. Electroanalysis,2008,20 (17),1839-1844.
[31]C. S. Shan, H. F. Yang, J. F. Song, D. X. Han, A. Ivaska, L. Niu, Direct electrochemistry of glucose oxidase and biosensing for glucose based on graphene. Anal. Chem.,2009,81 (6), 2378-2382.
[32]L. Wang, E. K. Wang, A novel hydrogen peroxide sensor based on horseradish peroxidase immobilized on colloidal Au modified ITO electrode. Electrochem. Commun.,2004,6 (2): 225-229.
[33]E. Rabinowitch, The photogalvanic properties of the thionine-iron system. J. Chem. Phys. 1940,8 (7),551-565.
[34]C. M. Ruan, R. Yang, X. H. Chen, J. Q. Deng, A reagentless amperometric hydrogen peroxide biosensor based on covalently binding horseradish peroxidase and thionine using a thiol-modified gold electrode. J. Electroanal. Chem.,1998,455 (1-2),121-125.
[35]N. D. Mermin, Crystalline order in two dimensions. Phys. Rev.,1968,176 (1),250-254.
[36]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature,2007,446,60-63.
[1]M. Pumera, Graphene-based nanomaterials and their electrochemistry. Chem. Soc. Rev.,2010, 39,4146-4157.
[2]D. Chen, L. H. Tang, J. H. Li, Graphene-based materials in electrochemistry. Chem. Soc. Rev., 2010,39,3157-3180.
[3]Y. Wang, Y. M. Li, L. H. Tang, J. Lu, J. H. Li, Application of graphene-modified electrode for selective detection of dopamine. Electrochem. Commun.,2009,11 (4),889-892.
[4]Y. Y Shao, J. Wang, H. Wu, J. Liu, I. A. Aksay, Y. H. Lin, Graphene based electrochemical sensors and biosensors:a review. Electroanalysis,2010,22 (10),1027-1036.
[5]J. J. Lu, S. Q. Liu, S. G. Ge, M. Yan, J. H. Yu, X. T. Hu, Ultrasensitive electrochemical immunosensor based on Au nanoparticles dotted carbon-nanotube-graphene composite and functionalized mesoporous materials. Biosens. Bioelectron.,2012,33 (1),29-35.
[6]K. S. Novoselov, D. Jiang, F. Schedin, T. J. Booth, V. V. Khotkevich, S. V. Morozov, A. K. Geim, Two-Dimensional atomic crystals. Proc. Natl. Aca. Sci.,2005,102 (30),10451-10453.
[7]A. K. Geim, K. S. Novoselov, The Rise of Graphene. Nat. Mater.,2007,6,183-191.
[8]A. Dato, V. Radmilovic, Z. Lee, J. Phillips, M. Frenklach, Substrate-free gas-phase synthesis of graphene sheets. Nano Lett.,2008,8 (7),2012-2016.
[9]C. Berger, Z. Song, X. Li, X. Wu, N. Brown, C. Naud, D. Mayou, T. Li, J. Hass, A. N. Marchenkov, E. H. Conrad, P. N. First, W. A. De Heer, Electronic confinement and coherence in patterned epitaxial graphene. Science,2006,312 (5777),1191-1196.
[10]P. W. Sutter, J. I. Flege, E. A. Sutter, Epitaxial graphene on ruthenium. Nat. Mater,2008,7, 406-411.
[11]S. Stankovich, D. A. Dikin, R. D. Piner, K. A. Kohlhaas, A. Kleinhammes, Y. Y. Jia, Y. Wu, S. T. Nguyen, R. S. Ruoff, Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide. Carbon,2007,45 (7),1558-1565.
[12]Y. C. Si, E. T. Samulski, Synthesis of water soluble graphene. Nano Lett.,2008,8 (6), 1679-1682.
[13]Y. Hernandez, V. Nicolosi, M. Lotya, F. M. Blighe, Z. Y. Sun, S. De, I. T. McGovern, B. Holland, M. Byrne, Y. K. Gun'ko, J. J. Boland, P. Niraj, G. Duesberg, S. Krishnamurthy, R. Goodhue, J. Hutchison, V. Scardaci, A. C. Ferrari, J. N. Coleman, High-yield production of graphene by liquid-phase exfoliation of Graphite. Nat. Nanotech.,2008,3,563-568.
[14]H. L. Guo, X. F. Wang, Q. Y. Qian, F. B. Wang, X. H. Xia, A green approach to the synthesis of graphene nanosheets. ACS Nano,2009,3 (9),2653-2659.
[15]Y. Y. Shao, J. Wang, M. Engelhard, C. M. Wang, Y. H. Lin, Facile and controllable electrochemical reduction of graphene oxide and its applications. J. Mater. Chem.,2010,20, 743-748.
[16]M. Zhou, Y. L. Wang, Y. M. Zhai, J. F. Zhai, W. Ren, F. Wang, S. J. Dong, Controlled synthesis of large-area and patterned electrochemically reduced graphene oxide films. Chem. Eur. J.,2009,15 (25),6116-6120.
[17]L. Y. Chen, Y. H. Tang, K. Wang, C. B. Liu, S. L. Luo, Direct electrodeposition of reduced graphene oxide on glassy carbon electrode and its electrochemical application. Electrochem. Commun.,2011,13 (2),133-137.
[18]A. Aresta, F. Palmisano, C. G. Zambonin, Simultaneous determination of caffeine, theobromine, theophylline, paraxanthine and nicotine in human milk by liquid chromatography with diode array UV detection. Food Chem.,2005,93 (1),177-181.
[19]N. Spataru, B. V. Sarada, D. A. Tryk, A. Fujishima, Anodic voltammetry of xanthine, theophylline, theobromine and caffeine at concuctive diamond electrodes and its analytical application. Electroanalysis,2002,14 (11),721-728.
[20]C. W. Zwillich, F. D. Sutton, T. A. Neff, W. M. Cohn, R. A. Matthay, M. M. Weinberger, Theophylline-induced seizures in adults. Correlation with serum concentrations. Annals of internal medicine,1975,82 (6),784-787.
[21]Q. S. Chen, Z. M. Guo, J. W. Zhao, Identification of green tea's (Camellia sinensis (L.)) quality level according to measurement of main catechins and caffeine contents by HPLC and support vector classification pattern recognition. J. Pharm. Biomed. Anal.,2008,48 (5), 1321-1325.
[22]V. Bellia, S. Battaglia, M. G. Matera, M. Cazzola, The use of bronchodilators in the treatment of airway obstruction in elderly patients. Pharmacol. Ther.,2006,19 (5),311-319.
[23]R. S. Nicholso, Theory and application of cyclic voltammetry for measurement of electrode reaction kinetics. Anal. Chem.,1965,37 (11),1351-1355.
[24]Y. Y. Shao, J. Wang, M. Engelhard, C. M. Wang, Y. H. Lin, Facile and controllable electrochemical reduction of graphene oxide and its applications. J. Mater. Chem.,2010,20, 743-748.
[25]N. G. Shang, P. Papakonstantinou, M. McMullan, M. Chu, A. Stamboulis, A. Potenza, S. S. Dhesi, H. Marchetto, Catalyst-free efficient growth, orientation and biosensing properties of multilayer graphene nanoflake films with sharp edge planes. Adv. Funct. Mater.,2008,18 (21), 3506-3514.
[26]P. H. Chen, M. A. Fryling, R. L. McCreery, Electron transfer kinetics at modified carbon electrode surfaces:the role of specific surface. Anal. Chem.,1995,67 (18),3115-3122.
[27]L. H. Tang, Y. Wang, Y. M. Li, H. B. Feng, J. Lu, J. H. Li, Preparation, structure, and electrochemical properties of reduced graphene sheet films. Adv. Funct. Mater.,2009,19 (17), 2782-2789.
[28]S. F. Hou, M. L. Kasner, S. J. Su, K. Patel, R. Cuellari, Highly sensitive and selective dopamine biosensor fabricated with silanized graphene. J. Phys. Chem. C,2010,114 (35), 14915-14921.
[29]S. Stankovich, R. D. Piner, X. Q. Chen, N. Q. Wu, S. T. Nguyen, R. S. Ruoff, Stable aqueous dispersions of graphitic nanoplatelets via the reduction of exfoliated graphite oxide in the presence of poly (sodium 4-styrenesulfonate). J. Mater. Chem.,2006,16,155-158.
[30]D. W. Boukhvalov, M. I. Katsnelson, Modeling of graphite oxide. J. Am. Chem. Soc.,2008, 130 (32),10697-10701.
[31]G. X. Wang, B. Wang, J. Park, J. Yang, X. P. Shen, J. Yao, Synthesis of enhanced hydrophilic and hydrophobic graphene oxide nanosheets by a solvothermal method. Carbon,2009, 47 (1),68-72.
[32]B. Brunetti, E. Desimoni, P. Casati, Determination of caffeine at a nafion-covered glassy carbon electrode. Electroanalysis,2007,19 (2-3),385-388.
[33]B. H. Hansen, G. Dryhurst, Electrochemical oxidation of theophylline at the pyrolytic graphite electrode. J. Electroanal. Chem.,1971,32 (3),405-414.
[34]N. Spataru, B. V. Sarada, D. A. Tryk, A. Fujishima, Caffeine at conductive diamond electrodes and its analytical application. Electroanalysis,2002,14 (11),721-728.
[35]L. Q. Liu, F. Xiao, J. W. Li, W. B. Wu, F. Q. Zhao, B. Z. Zeng, Platinum nanoparticles decorated multiwalled carbon nanotubes-ionic liquid composite film coated glassy carbon electrodes for sensitive determination of theophylline. Electroanalysis,2008,20 (11),1194-1199.
[36]H. W. Sun, F. X. Qiao, G Y. Liu, Characteristic of theophylline imprinted monolithic column and its application for determination of xanthine derivatives caffeine and theophylline in green tea. J. Chromatogr. A,2006,1134 (1-2),194-200.
[1]C. F. Ou, R. Yuan, Y. Q. Chai, M. Y. Tang, R. Chai, X. L. He, A novel amperometric immunosensor based on layer-by-layer assembly of gold nanoparticles-multi-walled carbon nanotubes-thionine multilayer films on polyelectrolyte surface. Analytica Chimica Acta.,2007, 603 (2),205-213.
[2]H. Li, Q. Wei, J. He, T. Li, Y. F. Zhao, Y. Y. Cai, B. Du, Z. Y. Qian, M. H. Yang, Electrochemical immunosensors for cancer biomarker with signal amplification based on ferrocene functionalized iron oxide nanoparticles. Biosens. Bioelectron.,2011,26 (8),3590-3595.
[3]K. Kerman, N. Nagatani, M. Chikae, T. K. Yuhi, Y. Takamura, E. Tamiya, Label-free electrochemical immunoassay for the detection of human chorionic gonadotropin hormone. Anal. Chem.,2006,78 (15),5612-5616.
[4]R. P. Liang, J. D. Qiu, P. X. Cai, A novel amperometric immunosensor based on three-dimensional sol-gel network and nanoparticle self-assemble technique. Anal. Chim. Acta., 2005,534 (2),223-229.
[5]Y. F. Zhao, Q. Wei, C. X. Xu, H. Li, D. Wu, Y. Y. Cai, K. X. Mao, Z. T. Cui, B. Du, Label-free electrochemical immunosensor for sensitive detection of kanamycin. Sens. Actuators, B,2011, 155 (2),618-625.
[6]Q. Wei, K. X. Mao, D. Wu, Y. X. Dai, J. Yang, B. Du, M. H. Yang, H. Li, A novel label-free electrochemical immunosensor based on graphene and thionine nanocomposite. Sens. Actuators, B,2010,149(1),314-318.
[7]X. Yu, B. Munge, V. Patel, G. Jensen, A. Bhirde, J. D. Gong, S. N. Kim, J. Gillespie, J. S. Gutkind, F. Papadimitrakopoulos, J. F. Rusling, Carbon nanotube amplification strategies for highly sensitive immunodetection of cancer biomarkers. J. Am. Chem. Soc.,2006,128 (34), 11199-11205.
[8]R. D. Miller, In search of low-k dielectrics. Science,1999,286 (5439),421-423.
[9]T. Yamata, H. S. Zhou, D. Hiroishi, M. Tomita, Y. Ueno, K. Asai, I. Honma, Platinum surface modification of SBA-15 by y-radiation treatment. Adv. Mater.,2003,15 (6),511-513.
[10]M. E. Davis, Ordered porous materials for emerging applications. Nature,2002,417, 813-821.
[11]J. Kim, J. E. Lee, J. Lee, J. H. Yu, B. C. Kim, K. An, Y. Hwang, C. H. Shin, J. G. Park, J. Kim, T. Hyeon, Magnetic fluorescent delivery vehicle using uniform mesoporous silica spheres embedded with monodisperse magnetic and semiconductor nanocrystals. J. Am. Chem. Soc.,2006, 128 (3),688-689.
[12]X. Feng, G. E. Fryxell, L. Q. Wang, A. Y. Kim, J. Liu, K. M. Kemner, Functionalized monolayers on ordered mesoporous supports. Science,1997,276 (5314),923-926.
[13]B. W. Park, D. Y. Yoon, D. S. Kim, Recent progress in bio-sensing technique with encapsulated enzymes. Biosens. Bioelectron.,2010,26 (1),1-10.
[14]J. F. Parker, C. A. Fields-Zinna, R. W. Murray, The story of a monodisperse gold nanoparticle:Au25Llg. Acc. Chem. Res.,2010,43 (9),1289-1296.
[15]X. L. Ren, X. W. Meng, F. Q. Tang, L. Zhan, Biosensor enhanced by glucose oxidase biomimetic membrane containing the platinum and silica nanoparticles. Mater. Sci. Eng. C.,2009, 29,2234-2238.
[16]C. X. Lei, F. C. Gong, G. L. Shen, R. Q. Yu, Amperometric immunosensor for schistosoma japonicum antigen using antibodies loaded on a nano-Au monolayer modified chitosan-entrapped carbon paste electrode. Sens. Actuators, B,2003,96 (3),582-588.
[17]R. Yang, C. M. Ruan, W. L. Dai, J. Q. Deng, J. L. Kong, Electropolymerization of thionone in neutral aqueous media and H2O2 biosensor based on poly(thionine). Electrochim. Acta,1999, 44(10),1585-1596.
[18]F. N. Xia, D. B. Farmer, Y. M. Lin, P. Avouris, Graphene field-effect transistors with high on/off current ratio and large transport band gap at room temperature. Nano Lett.,2010,10 (2), 715-718.
[19]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature,2007,446,60-63.
[20]J. H. Rouse, P. T. Lillehei, Electrostatic assembly of polymer/single walled carbon nanotube multilayer films. Nano Lett.,2003,3 (1),59-62.
[21]K. P. Liu, J. J. Zhang, C. M. Wang, J. J. Zhu, Graphene-assisted dual amplification strategy for the fabrication of sensitive amperometric immunosensor. Biosens. Bioelectron.,2011,26 (8), 3625-3632.
[22]C. J. Smith, P. C. Kelleher, Alpha-fetoprotein molecular heterogeneity. Physiologic correlations with normal growth, carcinogenesis and tumor growth. Biochim. Biophys. Acta,1980, 605 (1),1-32.
[23]H. Yokoo, T. Kondo, K. Fujii, T. Yamada, S. Todo, S. Hirohashi, Proteomic signature corresponding to alpha fetoprotein expression in liver cancer cells. Hepatology,2004,40 (3), 609-617.
[24]J. R. Gillespie, V. N. Uversky, Structure and function of a-fetoprotein:a biophysical overview. Biochim. Biophys. Acta,2000,1480 (1-2),41-56.
[25]J. J. Lu, S. Q. Liu, S. G. Ge, M. Yan, J. H. Yu, X. T. Hu, Ultrasensitive electrochemical immunosensor based on Au nanoparticles dotted carbon nanotube-graphene composite and functionalized mesoporous materials. Biosens. Bioelectron.,2012,33(1),29-35.
[26]Y. X. Fang, S. J. Guo, C. Z. Zhu, Y. M. Zhai, E. K. Wang, Self-assembly of cationic polyelectrolyte-functionalized graphene nanosheets and gold nanoparticles:a two-dimensional heterostructure for hydrogen peroxide sensing. Langmuir,2010,26 (13),11277-11282.
[27]S. Y. Wang, D. S. Yu, L. M. Dai, D. W. Chang, J. B. Baek, Polyelectrolyte-functionalized graphene as metal free electrocatalysts for oxygen reduction, ACS Nano,2011,5 (8),6202-6209.
[28]B. T. T. Nguyen, G. Koh, H. S. Lim, A. J. S. Chua, M. M. L. Ng, C. S. Toh, Membranebased electrochemical nanobiosensor for the detection of virus. Anal. Chem.,2009,81 (17),7226-7234.
[29]K. Kerman, N. Nagatani, M. Chikae, T. Yuhi, Y. Takamura, E. Tamiya, Labelfree electrochemical immunoassay for the detection of human chorionic gonadotropin hormone. Anal. Chem.,2006,78(15),5612-5616.
[2]C. G. Lee, X. D. Wei, J. W. Kysar, J. Hone, Measurement of the elastic properties and intrinsic strength of monolayer graphene. Science,2008,321 (5887),385-388.
[3]A. A. Balandin, S. Ghosh, W. Z. Bao, I. Calizo, D. Teweldebrhan, F. Miao, C. N. Lau, Superior thermal conductivity of single-layer graphene. Nano Letters.2008,8 (3),902-907.
[4]Z. H. Chen, Y. M. Lin, M. J. Rooks, P. Avouris, Graphene nano-ribbon electronics. Physica E: Low-dimensional systems and nanostructures,2007,40 (2),228-232.
[5]J. R. Dahn, T. Zheng, Y. H. Liu, J. S. Xue, Mechanisms for lithium insertion in carbonaceous materials. Science,1995,270 (5236),590-593.
[6]E. J. Yoo, J. Kim, E. Hosono, H. S. Zhou, T. Kudo, I. Honma, Large reversible Li storage of graphene nanosheet families for use in rechargeable lithium ion batteries. Nano Lett.,2008,8 (8), 2277-2282.
[7]K. S. Subrahmanyam, S. R. C. Vivekchand, A. Govindarai, C. N. R. Rao, A study of graphene prepared by different methods:characterization, properties and solubilization. J. Mater. Chem., 2008,18,1517-1523.
[8]K. S. Novoselov, A. K. Geim, S. V. Morozov et.al. Electric field effect in atomically thin carbon films. Science,2004,306 (5696),666-669.
[9]D. A. C. Brownson, C. E. Banks, Graphene electrochemistry:an overview of potential applications. Analyst.,2010,135,2768-2778.
[10]M. Pumera, Electrochemistry of graphene:new horizons for sensing and energy storage. The Chemical Record,2009,9 (4),211-223.
[11]D. K. Kampouris, C. E. Banks, Exploring the physicoelectrochemical properties of graphene. Chem. Commun.,2010,46,8986-8988.
[12]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature.,2007,446,60-63.
[13]A. K. Geim, K. S. Novoselov, The rise of graphene. Nature Materials.,2007,6,183-191.
[14]K. S. Kim, Y. Zhao, H. Jang, S. Y. Lee, J. M. Kim, K. S. Kim, J. H. Ahn, P. Kim, J. Y. Choi, B. H. Hong, Large-scale pattern growth of graphene films for stretchable transparent electrodes. Nature,2009,457,706-710.
[15]A. Dato, V. Radmilovic, Z. Lee, J. Phillips, M. Frenklach, Substrate-free gas-phase synthesis of graphene sheets. Nano Lett.,2008,8 (7),2012-2016.
[16]V. Borovikov, A. Zangwill. Step-edge instability during epitaxial growth of graphene from SiC (0001). Phys. Rev. B.,2009,80 (12):121406-121409.
[17]W. A. Heer, C. Berger, X. S. Wu, P. N. First, E. H. Conrad, X. B. Li, T. B. Li, M. Sprinkle, J. Hass, M. L. Sadowski, M. Potemski, G. Martinez, Epitaxial graphene. Solid State Commun.,2007, 143 (1-2):92-100.
[18]M. Sprinkle, P. Soukiassian, W. A. Heer, C. Berger, E. H. Conrad, Epitaxial graphene:the material for graphene electronics. Phys. Status Solidi (RRL)-Rapid Research Letters.,2009,3(6): A91-A94.
[19]J. B. Hannon, R. M. Tromp, Pit formation during graphene synthesis on SiC (0001):In situ electron microscopy. Phys. Rev. B.,2008,77(24):241404-241407.
[20]H. J. Shin, K. K. Kim, A. Benayad, S. M. Yoon, H. K. Park, I. S. Jung, M. H. Jin, H. Jeong, J. M. Kim, J. Y. Choi, Y. H. Lee, Efficient reduction of graphite oxide by sodium borohydride and its effect on electrical conductance. Adv Funct Mater.,2009,19 (12),1987-1992
[21]V. C. Tung, M. J. Allen, Y. Yang, R. B. Kaner, High-throughput solution processing of large-scale graphene. Nature Nanotechnology,2009,4(1),25-29
[22]M. Zhou, Y. L. Wang, Y. M. Zhai, J. F. Zhai, W. Ren, F. Wang, S. J. Dong, Controlled synthesis of large-area and patterned electrochemically reduced graphene oxide films. Chem. Eur. J.,2009,15 (25),6116-6120
[23]P. Steurer, R. Wissert, R. Thomann, R. Mulhaupt, Functionalized graphenes and thermoplastic nanocomposites based upon expanded graphite oxide. Macromol. Rapid Commun., 2009,30(4-5),316-327.
[24]H. C. Schniepp, J. L. Li, M. J. McAllister, H. Sai, M. Herrera-Alonso, D. H. Adamson, R. K. Prud'homme, R. Car, D. A. Saville, I. A. Aksay, Functionalized single graphene sheets derived from splitting graphite oxide. J. Phys. Chem. B,2006,110 (17),8535-8539.
[25]M. J. McAllister, J. L. Li, D. H. Adamson, H. C. Schniepp, A. A. Abdala, J. Liu, M. Herrera-Alonso, D. L. Milius, R. Car, R. K. Prud'homme, I. A. Aksay, Single sheet functionalized graphene by oxidation and thermal expansion of graphite. Chem. Mater.,2007,19 (18), 4396-4404.
[26]G. Williams, B. Seger, P. V. Kamat, TiO2-graphene nanocomposites. UV-assisted photocatalytic reduction of graphene oxide. Nano.,2008,2 (7),1487-1491.
[27]L. J. Cote, R. Cruz-Silva, J. X. Huang, Flash reduction and patterning of graphite oxide and its polymer composite. J. Am. Chem. Soc.,2009,131 (31),11027-11032.
[28]K. S. Subrahmanyam, L. S. Panchakarla, A. Govindaraj, C. N. R. Rao, Simple method of preparing graphene flakes by an Arc-Discharge method. J. Phys. Chem. C,2009,113 (11), 4257-4259.
[29]H. L. Qian, F. Negri, C. R. Wang, Z. H. Wang, Fully conjugated tri(perylene bisimides):an approach to the construction of n-type graphene nanoribbons. J. Am. Chem. Soc.,2008,130 (52), 17970-17976.
[30]C. E. Hamilton, J. R. Lomeda, Z. Z Sun, J. M. Tour, A. R. Barron, High-yield organic dispersions of unfunctionalized graphene. Nano Lett.,2009,9 (10),3460-3462.
[31]L. Y. Jiao, L. Zhang, X. R. Wang, G. Diankov, H. J. Dai, Narrow graphene nanoribbons from carbon nanotubes. Nature,2009,458,877-880.
[32]W. X. Zhang, J. C. Cui, C. A. Tao, Y. G. Wu, Z. P. Li, L. Ma, Y. Q. Wen, G. T. Li, A strategy for producing pure single-layer graphene sheets based on a confined self-assembly approach. Angewandte Chemie.,2009,121 (32):5978-5982.
[33]D. W. Boukhvalov, M. I. Katsnelson, Chemical functionalization of graphene. J. Phys.: Condens Matter,2009,21 (34) 344205-344216.
[34]H. Y. He, T. Riedl, A. Lerf, J. Klinowski, Solid-state NMR studies of the structure of graphite oxide. J. Phys. Chem.,1996,100 (51),19954-19958.
[35]H. Y. He, J. Klinowski, M. Forster, A. Lerf, A new structural model for graphite oxide. Chem. Phys. Lett.,1998,287 (1-2),53-56.
[36]A. Lerf, H. Y. He, M. Forster, J. Klinowski, Structure of graphite oxide revisited. J. Phys. Chem. B,1998,102 (23),4477-4482.
[37]W. W. Cai, R. D. Piner, F. J. Stadermann, S. J. Park, M. A. Shaibat, Y. Ishii, D. X. Yang, A. Velamakanni, S. J. An, M. Stoller, J. An, D. M. Chen, R. S. Ruoff, Synthesis and solid-state NMR structural characterization of 13C-labeled graphite oxide. Science,2008,321 (5897),1815-1817.
[38]S. Stankovich, R. D. Piner, X. Q. Chen, N. Q. Wu, S. T. Nguyen, R. S. Ruoff, Stable aqueous dispersions of graphitic nanoplatelets via the reduction of exfoliated graphite oxide in the presence of poly(sodium 4-styrenesulfonate). J. Mater. Chem.,2006,16,155-158
[39]Y. X. Xu, H. Bai, G. W. Lu, C. Li, G. Q. Shi. Flexible graphene films via the filtration of water-soluble noncovalent functionalized graphene sheets. J. Am. Chem. Soc.,2008,130 (18) 5856-5857.
[40]W. J. Hong, Y. X. Xu, G. W. Lu, C. Li, G. Q. Shi. Transparent graphene/PEDOT-PSS composite films as counter electrodes of dye-sensitized solar cells. Electrochem Commun.,2008, 10(10),1555-1558.
[41]C. Valles, C. Drummond, H. Saadaoui, C. A. Furtado, M. S. He, O. Roubeau, L. Ortolani, M. Monthioux, A. Penicaud. Solutions of negatively charged graphene sheets and ribbons. J. Am. Chem. Soc.,2008,130 (47),15802-15804.
[42]D. Li, M. B. Muller, S. Gilje, R. B. Kaner, G. G. Wallace. Processable aqueous dispersions of graphene nanosheets. Nat Nanotechnol.,2008,3,101-105.
[43]Y. Y. Liang, D. Q. Wu, X. L. Feng, K. Mullen, Dispersion of graphene sheets in organic solvent supported by ionic interactions. Adv Mater.,2009,21 (17),1679-1683.
[44]X. Y. Yang, Z. Y. Zhang, Z. F. Liu, Y. F. Ma, Y. Huang, Y. S. Chen. High-efficiency loading and controlled release of doxorubicin hydrochloride on graphene oxide. J. Phys. Chem. C,2008, 112(45),17554-17558.
[45]A. J. Patil, J. L. Vickery, T. B. Scott, S. Mann, Aqueous stabilization and self-assembly of graphene sheets into layered bio-nanocomposites using DNA. Adv. Mater.2009,21 (31), 3159-3164.
[46]S. Stankovich, R. D. Piner, S. T. Nguyen, R. S. Ruoff. Synthesis and exfoliation of isocyanate-treated graphene oxide nanoplatelets. Carbon,2006,44 (15),3342-3347.
[47]S. Niyogi, E. Bekyarova, M. E. Itkis, J. L. McWilliams, M. A. Hamon, R. C. Haddon. Solution properties of graphite and graphene. J. Am. Chem. Soc.,2006,128 (24),7720-7721.
[48]S. F. Hou, M. L. Kasner, S. J. Su, K. Patel, R. Cuellari. Highly sensitive and selective dopamine biosensor fabricated with silanized graphene. J. Phys. Chem. C,2010,114 (35), 14915-14921.
[49]J. F. Shen, Y. Z. Hu, C. Li, C. Qin, M. X. Ye. Synthesis of amphiphilic graphene nanoplatelets. Small,2009,5 (1),82-85.
[50]X. Y. Yang, X. Y. Zhang, Y. F. Ma, Y. Huang, Y. S. Wang, Y. S. Chen, Superparamagnetic graphene oxide-Fe3O4 nanoparticles hybrid for controlled targeted drug carriers. J. Mater. Chem., 2009,19,2710-2714.
[51]Y. X. Fang, S. J. Guo, C. Z. Zhu, Y. M. Zhai, E. K. Wang. Self-assembly of cationic polyelectrolyte-functionalized graphene nanosheets and gold nanoparticles:a two-dimensional heterostructure for hydrogen peroxide sensing. Langmuir.2010,26 (13),11277-11282.
[52]W. Chen, S. Chen, D. C. Qi, X. Y. Gao, A. T. S. Wee, Surface transfer p-type doping of epitaxial graphene. J. Am. Chem. Soc.,2007,129 (34),10418-10422.
[53]D. C. Wei, Y. Q. Liu, Y. Wang, H. L. Zhang, L. P. Huang, G. Yu, Synthesis of n-doped graphene by chemical vapor deposition and its electrical properties. Nano Lett.,2009,9 (5), 1752-1758.
[54]X. L. Li, H. L. Wang, J. T. Robinson, H. Sanchez, G. Diankov, H. J. Dai, Simultaneous nitrogen doping and reduction of graphene oxide. J. Am. Chem. Soc.,2009,131 (43), 15939-15944.
[55]K. S. Subrahmanyam, L. S. Panchakarla, A. Govindaraj, C. N. R. Rao, Simple method of preparing graphene flakes by an Arc-discharge method. J. Phys. Chem. C,2009,113 (11), 4257-4259.
[56]N. Li, Z. Y. Wang, K. K. Zhao, Z. J. Shi, Z. N. Gu, S. K. Xu, Large scale synthesis of N-doped multi-layered graphene sheets by simple arc-discharge method. Carbon,2010,48 (1), 255-259.
[57]S. B. Yang, G. L. Cui, S. P. Pang, Q. Cao, U. Kolb, X. L. Feng, J. Maier, K. Mullen, Fabrication of cobalt and cobalt oxide/graphene composites:towards high-performance anode materials for lithium ion batteries. Chem. Sus. Chem.,2010,3 (2),236-239.
[58]G. X. Wang, X. P. Shen, J. Yao, J. Park, Graphene nanosheets for enhanced lithium storage in lithium ion batteries. Carbon.2009,47 (8),2049-2053.
[59]W. Lv, D. M. Tang, Y. B. He, C. H. You, Z. Q. Shi, X. C. Chen, C. M. Chen, P. X. Hou, C. Liu, Q. H. Yang, Low-temperature exfoliated graphenes:vacuum-promoted exfoliation and electrochemical energy storage. ACS Nano,2009,3 (11),3730-3736.
[60]Y. Chen, X. Zhang, P. Yu, Y. W. Ma, Electrophoretic deposition of graphene nanosheets on nickel foams for electrochemical capacitors. Journal of Power Sources,2010,195 (9),3031-3035.
[61]Z. Liu, J. T. Robinson, X. M. Sun, H. J. Dai, PEGylated nanographene oxide for delivery of water-insoluble cancer drugs. J. Am. Chem. Soc.,2008,130 (33):10876-10877.
[62]X. Y. Yang, X. Y. Zhang, Z. F. Liu, Y. F. Ma, Y. Huang, Y. S. Chen, High-efficiency loading and controlled release of doxorubicin hydrochloride on graphene oxide. J. Phys. Chem. C.,2008, 112(45),17554-17558.
[63]P. Ramesh, S. Bhagyalakshmi, S. Sampath, Preparation and physicochemical and electrochemical characterization of exfoliated graphite oxide. J. Colloid Interface Sci.,2004,274 (1),95-102.
[64]F. Schedin, A. K. Geim, S. V. Morozov, E. W. Hill, P. Blake, M. I. Katsnelson, K. S. Novoselov, Detection of individual gas molecules adsorbed on graphene. Nat. Mater.,2007,6, 652-655.
[1]W. R. Yang, K. R. Ratinac, S. P. Ringer, P. Thordarson, J. J. Gooding, F. Braet, Carbon nanomaterials in biosensors:should you use nanotubes or graphene. Angew. Chem. Int. Ed.,2010, 49 (12),2114-2138.
[2]A. K. Geim, K. S. Novoselov, The rise of graphene. Nat. Mater.,2007,6,183-191.
[3]M. Pumera, Electrochemistry of graphene:new horizons for sensing and energy storage. Chem. Rec.,2009,9 (4),211-223.
[4]M. H. Liang, L. J. Zhi, Graphene-based electrode materials for rechargeable lithium batteries. J. Mater. Chem.,2009,19,5871-5878.
[5]Y. Y. Shao, J. Wang, H. Wu, J. Liu, I. A. Aksay, Y. H. Lin, Graphene based electrochemical sensors and biosensors:a review. Electroanal.,2010,22 (10),1027-1036.
[6]Z. J. Wang, X. Z. Zhou, J. Zhang, F. Boey, H. Zhang, Direct electrochemical reduction of single-layer graphene oxide and subsequent functionalization with glucose oxidase. J. Phys. Chem. C,2009,113 (32) 14071-14075.
[7]Y. Wang, Y. M. Li, L. H. Tang, J. Lu, J. H. Li, Application of graphene-modified electrode for selective detection of dopamine. Electrochem. Commun.,2009,11 (4) 889-892.
[8]C. Wang, L. Zhang, Z. H. Guo, J. G. Xu, H. Y. Wang, K. F. Zhai, X. Zhuo, A novel hydrazine electrochemical sensor based on the high specifiec area graphene. Microchim. Acta,2010,169 (1-2),1-6.
[9]C. S. Shan, H. F. Yang, D. X. Han, Q. X. Zhang, A. Ivaska, L. Niu, Water-soluble graphene covalently functionalized by biocompatible poly-L-lysine. Langmuir,2009,25 (20),12030-12033.
[10]D. Li, M. B. Miiller, S. Gilje, R. B. Kaner, G. G. Wallace, Processable aqueous dispersions of graphene nanosheets. Nat. Nanotechnol.,2008,3,101-105.
[11]Y. C. Si, E. T. Samulski, Synthesis of water soluble graphene. Nano Lett.,2008,8 (6), 1679-1682.
[12]Y. Y. Liang, D. Q. Wu, X. L. Feng, K. Mullen, Dispersion of graphene sheets in organic solvent supported by ionic interactions. Adv. Mater.,2009,21 (17),1679-1683.
[13]S. Stankovich, R. D. Piner, X. Q. Chen, N. Q. Wu, S. T. Nguyen, R. S. Ruoff, Stable aqueous dispersions of graphitic nanoplatelets via the reduction of exfoliated graphite oxide in the presence of poly(sodium 4-styrenesulfonate). J. Mater. Chem.,2006,16,155-158.
[14]X. B. Fan, W. C. Peng, Y. Li, X. Y. Li, S. L. Wang, G. L. Zhang, F. B. Zhang, Deoxygenation of exfoliated graphite oxide under alkaline conditions:a green route to graphene preparation. Adv. Mater.,2008,20 (23),4490-4493.
[15]S. Stankovich, D. A. Dikin, G. H. B. Dommett, K. M. Kohlhaas, E. J. Zimney, E. A. Stach, R. D. Piner, S. T. Nguyen, R. S. Ruoff, Graphene-based composite materials. Nature,2006,442, 282-286.
[16]A. P. Yu, P. Ramesh, M. E. Itkis, E. Bekyarova, R. C. Haddon, Graphite nanoplatelet-epoxy composite thermal interface materials. J. Phys. Chem. C,2007,111 (21),7565-7569.
[17]Y. C. Si, E. T. Samulski, Exfoliated graphene separated by platinum nanoparticles. Chem. Mater.,2008,20 (21),6792-6797.
[18]R. Muszynski, B. Seger, P. V. Kamat, Decorating graphene sheets with gold nanoparticles. J. Phys. Chem. C,2008,112 (14),5263-5266.
[19]C. Xu, X. Wang, J. W. Zhu, Graphene-metal particle nanocomposites. J. Phys. Chem. C, 2008,112(50),19841-19845.
[20]C. M. Shen, C. Hui, T. Z. Yang, C. W. Xiao, J. F. Tian, L. H. Bao, S. T. Chen, H. Ding, H. J. Gao, Monodisperse noble-metal nanoparticles and their surface enhanced raman scattering properties. Chem. Mater.,2008,20 (22),6939-6944.
[21]Y. X. Fang, S. J. Guo, C. Z. Zhu, Y. M. Zhai, E. K. Wang, Self-assembly of cationic polyelectrolyte-funcionalized graphene nanosheets and gold nanoparticles:a two-dimensional heterostructure for hydrogen peroxide sensing. Langmuir,2010,26 (13),11277-11282.
[22]F. Liu, J. Y. Choi, T. S. Seo, DNA mediated water-dispersible graphene fabrication and gold nanoparticle-graphene hybrid. Chem. Commun.,2010,46,2844-2846.
[23]W. J. Hong, H. Bai, Y. X. Xu, Z. Y. Yao, Z. Z. Gu, G. Q. Shi, Preparation of gold nanoparticle/graphene composites with controlled weight contents and their application in biosensors. J. Phys. Chem. C,2010,114 (4),1822-1826.
[24]J. B. Liu, S. H. Fu, B. Yuan, Y. L. Li, Z. X. Deng, Toward a universal "adhesive nanosheet" for the assembly of multiple nanoparticles based on a protein-induced reduction/decoration of graphene oxide. J. Am. Chem. Soc.,2010,132 (21),7279-7281.
[25]Y. K. Kim, H. K. Na, D. H. Min, Influence of surface functionalization on the growth of gold nanostructures on graphene thin films. Langmuir,2010,26 (16) 13065-13070.
[26]G. Goncalves, P. A. A. P. Marques, C. M. Granadeiro, H. I. S. Nogueira, M. K. Singh, J. Gracio, Surface modification of graphene nanosheets with gold nanoparticles:the role of oxygen moieties at graphene surface on gold nucleation and growth. Chem. Mater.,2009,21 (20), 4796-4802.
[27]B. S. Kong, J. X. Geng, H. T. Jung, Layer-by-layer assembly of graphene and gold nanoparticles by vacuum filtration and spontaneous reduction of gold ions. Chem. Commun.,2009, 16,2174-2176.
[28]W. A. Banks, Enhanced leptin transport across the blood-brain barrier by al-adrenergic agents. Brain Res.,2001,899 (1-2),209-217.
[29]J. O. Schenk, E. Miller, R. N. Adams, Electrochemical techniques for the study of brain chemistry. J. Chem. Educ.,1983,60 (4) 311-315.
[30]Y. Hasebe, T. Hirano, S. Uchiyama, Determination of catecholamines and uric acid in biological fluids without pretreatment, using chemically amplified biosensors. Sens. Actuators, B, 1995,24 (1-3),94-97.
[31]T. Luczak, Comparison of electrochemical oxidation of epinephrine in the presence of interfering ascorbic and uric acids on gold electrodes modified with S-functionalized compounds and gold nanoparticles. Electrochim. Acta,2009,54 (24) 5863-5870.
[32]A. Sucheta, J. Rusling, Effect of background charge on estimating diffusion coefficients by chronocoulometry at glassy carbon electrodes. Electroanal.,1991,3 (8) 735-739.
[33]X.Z. Wu, L.J. Mu, W.Z. Zhang, Impedance of the electrochemical oxidation of epinephrine on a glassy carbon electrode. J. Electroanal. Chem.,1993,352 (1-2),295-300.
[34]E. L. Ciolkowski, K. M. Maness, P. S. Cahill, R. M. Wightman, D. H. Evans, B. Fosset, C. Amatore, Disproportionation during electrooxidation of catecholamines at carbon-fiber microelectrodes. Anal. Chem.,1994,66 (21) 3611-3617.
[35]M. D. Hawley, S. V. Tatawawadi, S. Piekarski, R. N. Adams, Electrochemical studies of the oxidation pathways of catecholamines. J. Am. Chem. Soc.,1967,89 (2) 447-450.
[36]H. S. Wang, D. Q. Huang, R. M. Liu, Study on the electrochemical behavior of epinephrine at a poly(3-methylthiophene)-modified glassy carbon electrode. J. Electroanal. Chem.,2004,570 (1) 83-90.
[37]H. M. Zhang, X. L. Zhou, R. T. Hui, N. Q. Li, D. P. Liu, Studies of the electrochemical behavior of epinephrine at a homocysteine self-assembled electrode. Talanta,2002,56 (6), 1081-1088.
[38]M. Zhu, X. M. Huang, J. Li, H. X. Shen, Peroxidase-based spectrophotometric methods for the determination of ascorbic acid, norepinephrine, epinephrine, dopamine and levodopa. Anal. Chim. Acta,1997,357 (3),261-267.
[39]K. C. Grabar, R. Griffith Freeman, M. B. Hommer, M. J. Natan, Preparation and characterization of Au colloid monolayers. Anal. Chem.,1995,67 (4) 735-743.
[40]R. J. Bowling, R. T. Packard, R. L. McCreery, Activation of highly ordered pyrolytic graphite for heterogeneous electron transfer:relationship between electrochemical performance and carbon microstructure. J. Am. Chem. Soc.,1989,111 (4),1217-1223.
[41]S. Stankovich, D. A. Dikin, R. D. Piner, K. A. Kohlhass, A. Kleinhammes, Y. Y. Jia, Y. Wu, S. T. Nguyen, R. S. Ruoff, Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide. Carbon,2007,45 (7),1558-1565.
[42]K. N. Kudin, B. Ozbas, H. C. Schniepp, R. K. Prud'homme, I. A. Aksay, R. Car, Raman spectra of graphite oxide and functionalized graphene sheets. Nano Lett.,2008,8 (1) 36-41.
[43]N. D. Mermin, Crystalline order in two dimensions. Phys. Rev.,1968,176 (1),250-254.
[44]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature,2007,446,60-63.
[45]L. Han, X. L. Zhang, Simultaneous voltammetric determination of dihydroxybenzene isomers by nanogold modified electrode. Electroanalysis,2009,21 (2),124-129.
[46]T. Komura, G. Y. Niu, T. Yamaguchi, M. Asano, A. Matsuda, Coupled electron-proton transport in electropolymerized methylene blue and the influences of its protonation level on the rate of electron exchange with β-nicotinamide adenine dinucleotide. Electroanal.,2004,16 (21), 1791-1800.
[47]U. Yogeswaran, S. Thiagarajan, S. M. Chen, Pinecone shape hydroxypropyl-β-cyclodextrin on a film of multi-walled carbon nanotubes coated with gold particles for the simultaneous determination of tyrosine, guanine, adenine and thymine. Carbon,2007,45(14),2783-2796.
[1]T. Seyller, A. Bostwick, K. V. Emtsev, K. Horn, L. Ley, J. L. McChesney, T. Ohta, J. D. Riley, E. Rotenberg, F. Speck, Epitaxial graphene:a new material. Phys. Stat. Sol. B,2008,245 (7), 1436-1446.
[2]C. N. R. Rao, A. K. Sood, K. S. Subrahmanyam, A. Govindaraj, Graphene:The new two-dimensional nanomaterial. Angew. Chem. Int. Ed.,2009,48 (42),7752-7777.
[3]L. H. Tang, Y. Wang, Y. M. Li, H. B. Feng, J. Lu, J. H. Li, Preparation, structure and electrochemical properties of reduced graphene sheet films. Adv. Funct. Mater.,2009,19 (17), 2782-2789.
[4]C. S. Shan, H. F. Yang, J. F. Song, D. X. Han, A. Ivaska, L. Niu, Direct electrochemistry of glucose oxidase and biosensing for glucose based on graphene. Anal. Chem.,2009,81 (6), 2378-2382.
[5]H. Q. Chen, M. B. Miiller, K. J. Gilmore, G. G. Wallace, D. Li, Mechanically strong, electrically conductive, and biocompatible graphene paper. Adv. Mater.,2008,20 (18), 3557-3561.
[6]Y. Wang, Y. M. Li, L. H. Tang, J. Lu, J. H. Li, Application of graphene-modified electrode for selective detection of dopamine. Electrochem. Commun.,2009,11 (4),889-892.
[7]F. H. Li, J. Chai, H. F. Yang, D. X. Han, L. Niu, Synthesis of Pt/ionic liquid/graphene nanocomposite and its simultaneous determination of ascorbic acid and dopamine.2010,81 (3), 1063-1068.
[8]H. K. He, C. Gao, Graphene nanosheets decorated with Pd, Pt, Au, and Ag nanoparticles: synthesis, characterization and catalysis applications. Science China Chemistry,2011,54 (2), 397-404.
[9]Y. Chen, Y. Li, D. Sun, D. B. Tian, J. R. Zhang, J. J. Zhu, Fabrication of gold nanoparticles on bilayer graphene for glucose electrochemical biosensing. J. Mater. Chem.,2011,21,7604-7611.
[10]F. Liu, J. Y. Choi, T. S. Seo, DNA mediated water-dispersible graphene fabrication and gold nanoparticle-graphene hybrid. Chem. Commun.,2010,46,2844-2846.
[11]T. A. Pham, B. C. Choi, K. T. Lim, Y. T. Jeong, A simple approach for immobilization of gold nanoparticles on graphene oxide sheets by covalent bonding. Appl. Surf. Sci.,257 (8), 3350-3357.
[12]J. B. Liu, S. H. Fu, B. Yuan, Y. L. Li, Z. X. Deng, Toward a universal "adhesive nanosheet" for the assembly of multiple nanoparticles based on a protein-induced reduction/decoration of graphene oxide. J. Am. Chem. Soc.,2010,132 (21),7279-7281.
[13]G. Goncalves, P. A. A. P. Marques, C. M. Granadeiro, H. I. S. Nogueira, M. K. Singh, J. Gracio, Surface modification of graphene nanosheets with gold nanoparticles:the role of oxygen moieties at graphene surface on gold micleation and growth. Chem. Mater.,2009,21 (20), 4796-4802.
[14]B. S. Kong, J. X. Geng, H. T. Jung, Layer-by-layer assembly of graphene and gold nanoparticles by vacuum filtration and spontaneous reduction of gold ions. Chem. Commun.,2009, 16,2174-2176.
[15]X. S. Zhou, T. B. Wu, K. L. Ding, B. J. Hu, M. Q. Hou, B. X. Han, Dispersion of graphene sheets in ionic liquid [bmim][PF6] stabilized by an ionic liquid polymer. Chem. Commun.,2010, 46,386-388.
[16]H. Shobukawa, H. Tokuda, M. A. B. H. Susan, M. Watanabe, Ion transport properties of lithium ionic liquids and their ion gels. Electrochim. Acta,2005,50 (19),3872-3877.
[17]P. A. Z. Suarez, V. M. Selbach, J. E. L. Dullius, S. Einloft, C. M. S. Piatnicki, D. S. Azambuja, R. F. Souza, J. Dupont, Enlarged electrochemical window in dialkyl-imidazolium cation based room-temperature air and water-stable molten salts. Electrochim. Acta,1997,42 (16),2533-2535.
[18]H. Shobukawa, H. Tokuda, S. I. Tabata, M. Watanabe, Preparation and transport properties of novel lithium ionic liquids. Electrochim. Acta,2004,50 (2-3),305-309.
[19]T. Fujimoto, M. M. Matsushita, H. Yoshikawa, K. Awaga, Electrochemical and electrochromic properties of octathio circulene thin films in ionic liquids. J. Am. Chem. Soc., 2008,130 (47),15790-15791.
[20]N. Liu, F. Luo, H. X. Wu, Y. H. Liu, C. Zhang, J. Chen, One-step ionic-liquid-assisted electrochemical synthesis of ionic-liquidfunctionalized graphene sheets directly from graphite. Adv. Funct. Mater.,2008,18 (10),1518-1525.
[21]X. B. Lu, Q. Zhang, L. Zhang, J. H. Li, Direct electron transfer of horseradish peroxidase and its biosensor based on chitosan and room temperature ionic liquid. Electrochem. Commun.,2006, 8 (5),874-878.
[22]N. Maleki, A. Safavi, F. Tajabadi, High-performance carbon composite electrode based on an ionic liquid as a binder. Anal. Chem.,2006,78 (11),3820-3826.
[23]W. Sun, D. D. Wang, R. F. Gao, K. Jiao, Direct electrochemistry and electrocatalysis of hemoglobin in sodium alginate film on a [BMIM][PF6] modified carbon paste electrode. Electrochem. Commun.,2007,9 (5),1159-1164.
[24]D. Wei and A. Ivaska, Applications of ionic liquids in electrochemical sensors. Anal. Chim. Acta,2008,607 (2),126-135.
[25]J. Kulys, L. Z. Wang, A. Maksimoviene, L-Lactate oxidase electrode based on methylene green and carbon paste. Anal. Chim. Acta,1993,274 (1),53-58.
[26]K. Yamamoto, T. Ohgaru, M. Torimura, H. Kinoshita, K. Kano, T. Ikeda, Highly-sensitive flow injection determination of hydrogen peroxide with a peroxidase-immobilized electrode and its application to clinical chemistry. Anal. Chim. Acta,2000,406 (2),201-207.
[27]沈友,柴素芬.碘-四氯化碳萃取光度法间接测定食品中的痕量过氧化氢。光谱实验室,2003,20(4),636-638。
[28]S. Sakura, Electrochemiluminescence of hydrogen peroxide-luminol at a carbon electrode. Anal. Chim. Acta,1992,262 (1),49-57.
[29]Q. Y. Chen, D. H. Li, Q. Z. Zhu, H. Zheng, J. G. Xu, Application of iron-tetrasulfonatophthalocyanine as a new mimetic peroxidase in the determination of hydrogen peroxide with p-hydroxyphenylpropionic acid as a substrate. Anal. Chim. Acta,1999,381 (2-3), 175-182.
[30]P. X. Yuan, Y. Zhuo, Y. Q. Chai, H. X. Ju, Dendritic silver/silicon dioxide nanocomposite modified electrodes for electrochemical sensing of hydrogen peroxide. Electroanalysis,2008,20 (17),1839-1844.
[31]C. S. Shan, H. F. Yang, J. F. Song, D. X. Han, A. Ivaska, L. Niu, Direct electrochemistry of glucose oxidase and biosensing for glucose based on graphene. Anal. Chem.,2009,81 (6), 2378-2382.
[32]L. Wang, E. K. Wang, A novel hydrogen peroxide sensor based on horseradish peroxidase immobilized on colloidal Au modified ITO electrode. Electrochem. Commun.,2004,6 (2): 225-229.
[33]E. Rabinowitch, The photogalvanic properties of the thionine-iron system. J. Chem. Phys. 1940,8 (7),551-565.
[34]C. M. Ruan, R. Yang, X. H. Chen, J. Q. Deng, A reagentless amperometric hydrogen peroxide biosensor based on covalently binding horseradish peroxidase and thionine using a thiol-modified gold electrode. J. Electroanal. Chem.,1998,455 (1-2),121-125.
[35]N. D. Mermin, Crystalline order in two dimensions. Phys. Rev.,1968,176 (1),250-254.
[36]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature,2007,446,60-63.
[1]M. Pumera, Graphene-based nanomaterials and their electrochemistry. Chem. Soc. Rev.,2010, 39,4146-4157.
[2]D. Chen, L. H. Tang, J. H. Li, Graphene-based materials in electrochemistry. Chem. Soc. Rev., 2010,39,3157-3180.
[3]Y. Wang, Y. M. Li, L. H. Tang, J. Lu, J. H. Li, Application of graphene-modified electrode for selective detection of dopamine. Electrochem. Commun.,2009,11 (4),889-892.
[4]Y. Y Shao, J. Wang, H. Wu, J. Liu, I. A. Aksay, Y. H. Lin, Graphene based electrochemical sensors and biosensors:a review. Electroanalysis,2010,22 (10),1027-1036.
[5]J. J. Lu, S. Q. Liu, S. G. Ge, M. Yan, J. H. Yu, X. T. Hu, Ultrasensitive electrochemical immunosensor based on Au nanoparticles dotted carbon-nanotube-graphene composite and functionalized mesoporous materials. Biosens. Bioelectron.,2012,33 (1),29-35.
[6]K. S. Novoselov, D. Jiang, F. Schedin, T. J. Booth, V. V. Khotkevich, S. V. Morozov, A. K. Geim, Two-Dimensional atomic crystals. Proc. Natl. Aca. Sci.,2005,102 (30),10451-10453.
[7]A. K. Geim, K. S. Novoselov, The Rise of Graphene. Nat. Mater.,2007,6,183-191.
[8]A. Dato, V. Radmilovic, Z. Lee, J. Phillips, M. Frenklach, Substrate-free gas-phase synthesis of graphene sheets. Nano Lett.,2008,8 (7),2012-2016.
[9]C. Berger, Z. Song, X. Li, X. Wu, N. Brown, C. Naud, D. Mayou, T. Li, J. Hass, A. N. Marchenkov, E. H. Conrad, P. N. First, W. A. De Heer, Electronic confinement and coherence in patterned epitaxial graphene. Science,2006,312 (5777),1191-1196.
[10]P. W. Sutter, J. I. Flege, E. A. Sutter, Epitaxial graphene on ruthenium. Nat. Mater,2008,7, 406-411.
[11]S. Stankovich, D. A. Dikin, R. D. Piner, K. A. Kohlhaas, A. Kleinhammes, Y. Y. Jia, Y. Wu, S. T. Nguyen, R. S. Ruoff, Synthesis of graphene-based nanosheets via chemical reduction of exfoliated graphite oxide. Carbon,2007,45 (7),1558-1565.
[12]Y. C. Si, E. T. Samulski, Synthesis of water soluble graphene. Nano Lett.,2008,8 (6), 1679-1682.
[13]Y. Hernandez, V. Nicolosi, M. Lotya, F. M. Blighe, Z. Y. Sun, S. De, I. T. McGovern, B. Holland, M. Byrne, Y. K. Gun'ko, J. J. Boland, P. Niraj, G. Duesberg, S. Krishnamurthy, R. Goodhue, J. Hutchison, V. Scardaci, A. C. Ferrari, J. N. Coleman, High-yield production of graphene by liquid-phase exfoliation of Graphite. Nat. Nanotech.,2008,3,563-568.
[14]H. L. Guo, X. F. Wang, Q. Y. Qian, F. B. Wang, X. H. Xia, A green approach to the synthesis of graphene nanosheets. ACS Nano,2009,3 (9),2653-2659.
[15]Y. Y. Shao, J. Wang, M. Engelhard, C. M. Wang, Y. H. Lin, Facile and controllable electrochemical reduction of graphene oxide and its applications. J. Mater. Chem.,2010,20, 743-748.
[16]M. Zhou, Y. L. Wang, Y. M. Zhai, J. F. Zhai, W. Ren, F. Wang, S. J. Dong, Controlled synthesis of large-area and patterned electrochemically reduced graphene oxide films. Chem. Eur. J.,2009,15 (25),6116-6120.
[17]L. Y. Chen, Y. H. Tang, K. Wang, C. B. Liu, S. L. Luo, Direct electrodeposition of reduced graphene oxide on glassy carbon electrode and its electrochemical application. Electrochem. Commun.,2011,13 (2),133-137.
[18]A. Aresta, F. Palmisano, C. G. Zambonin, Simultaneous determination of caffeine, theobromine, theophylline, paraxanthine and nicotine in human milk by liquid chromatography with diode array UV detection. Food Chem.,2005,93 (1),177-181.
[19]N. Spataru, B. V. Sarada, D. A. Tryk, A. Fujishima, Anodic voltammetry of xanthine, theophylline, theobromine and caffeine at concuctive diamond electrodes and its analytical application. Electroanalysis,2002,14 (11),721-728.
[20]C. W. Zwillich, F. D. Sutton, T. A. Neff, W. M. Cohn, R. A. Matthay, M. M. Weinberger, Theophylline-induced seizures in adults. Correlation with serum concentrations. Annals of internal medicine,1975,82 (6),784-787.
[21]Q. S. Chen, Z. M. Guo, J. W. Zhao, Identification of green tea's (Camellia sinensis (L.)) quality level according to measurement of main catechins and caffeine contents by HPLC and support vector classification pattern recognition. J. Pharm. Biomed. Anal.,2008,48 (5), 1321-1325.
[22]V. Bellia, S. Battaglia, M. G. Matera, M. Cazzola, The use of bronchodilators in the treatment of airway obstruction in elderly patients. Pharmacol. Ther.,2006,19 (5),311-319.
[23]R. S. Nicholso, Theory and application of cyclic voltammetry for measurement of electrode reaction kinetics. Anal. Chem.,1965,37 (11),1351-1355.
[24]Y. Y. Shao, J. Wang, M. Engelhard, C. M. Wang, Y. H. Lin, Facile and controllable electrochemical reduction of graphene oxide and its applications. J. Mater. Chem.,2010,20, 743-748.
[25]N. G. Shang, P. Papakonstantinou, M. McMullan, M. Chu, A. Stamboulis, A. Potenza, S. S. Dhesi, H. Marchetto, Catalyst-free efficient growth, orientation and biosensing properties of multilayer graphene nanoflake films with sharp edge planes. Adv. Funct. Mater.,2008,18 (21), 3506-3514.
[26]P. H. Chen, M. A. Fryling, R. L. McCreery, Electron transfer kinetics at modified carbon electrode surfaces:the role of specific surface. Anal. Chem.,1995,67 (18),3115-3122.
[27]L. H. Tang, Y. Wang, Y. M. Li, H. B. Feng, J. Lu, J. H. Li, Preparation, structure, and electrochemical properties of reduced graphene sheet films. Adv. Funct. Mater.,2009,19 (17), 2782-2789.
[28]S. F. Hou, M. L. Kasner, S. J. Su, K. Patel, R. Cuellari, Highly sensitive and selective dopamine biosensor fabricated with silanized graphene. J. Phys. Chem. C,2010,114 (35), 14915-14921.
[29]S. Stankovich, R. D. Piner, X. Q. Chen, N. Q. Wu, S. T. Nguyen, R. S. Ruoff, Stable aqueous dispersions of graphitic nanoplatelets via the reduction of exfoliated graphite oxide in the presence of poly (sodium 4-styrenesulfonate). J. Mater. Chem.,2006,16,155-158.
[30]D. W. Boukhvalov, M. I. Katsnelson, Modeling of graphite oxide. J. Am. Chem. Soc.,2008, 130 (32),10697-10701.
[31]G. X. Wang, B. Wang, J. Park, J. Yang, X. P. Shen, J. Yao, Synthesis of enhanced hydrophilic and hydrophobic graphene oxide nanosheets by a solvothermal method. Carbon,2009, 47 (1),68-72.
[32]B. Brunetti, E. Desimoni, P. Casati, Determination of caffeine at a nafion-covered glassy carbon electrode. Electroanalysis,2007,19 (2-3),385-388.
[33]B. H. Hansen, G. Dryhurst, Electrochemical oxidation of theophylline at the pyrolytic graphite electrode. J. Electroanal. Chem.,1971,32 (3),405-414.
[34]N. Spataru, B. V. Sarada, D. A. Tryk, A. Fujishima, Caffeine at conductive diamond electrodes and its analytical application. Electroanalysis,2002,14 (11),721-728.
[35]L. Q. Liu, F. Xiao, J. W. Li, W. B. Wu, F. Q. Zhao, B. Z. Zeng, Platinum nanoparticles decorated multiwalled carbon nanotubes-ionic liquid composite film coated glassy carbon electrodes for sensitive determination of theophylline. Electroanalysis,2008,20 (11),1194-1199.
[36]H. W. Sun, F. X. Qiao, G Y. Liu, Characteristic of theophylline imprinted monolithic column and its application for determination of xanthine derivatives caffeine and theophylline in green tea. J. Chromatogr. A,2006,1134 (1-2),194-200.
[1]C. F. Ou, R. Yuan, Y. Q. Chai, M. Y. Tang, R. Chai, X. L. He, A novel amperometric immunosensor based on layer-by-layer assembly of gold nanoparticles-multi-walled carbon nanotubes-thionine multilayer films on polyelectrolyte surface. Analytica Chimica Acta.,2007, 603 (2),205-213.
[2]H. Li, Q. Wei, J. He, T. Li, Y. F. Zhao, Y. Y. Cai, B. Du, Z. Y. Qian, M. H. Yang, Electrochemical immunosensors for cancer biomarker with signal amplification based on ferrocene functionalized iron oxide nanoparticles. Biosens. Bioelectron.,2011,26 (8),3590-3595.
[3]K. Kerman, N. Nagatani, M. Chikae, T. K. Yuhi, Y. Takamura, E. Tamiya, Label-free electrochemical immunoassay for the detection of human chorionic gonadotropin hormone. Anal. Chem.,2006,78 (15),5612-5616.
[4]R. P. Liang, J. D. Qiu, P. X. Cai, A novel amperometric immunosensor based on three-dimensional sol-gel network and nanoparticle self-assemble technique. Anal. Chim. Acta., 2005,534 (2),223-229.
[5]Y. F. Zhao, Q. Wei, C. X. Xu, H. Li, D. Wu, Y. Y. Cai, K. X. Mao, Z. T. Cui, B. Du, Label-free electrochemical immunosensor for sensitive detection of kanamycin. Sens. Actuators, B,2011, 155 (2),618-625.
[6]Q. Wei, K. X. Mao, D. Wu, Y. X. Dai, J. Yang, B. Du, M. H. Yang, H. Li, A novel label-free electrochemical immunosensor based on graphene and thionine nanocomposite. Sens. Actuators, B,2010,149(1),314-318.
[7]X. Yu, B. Munge, V. Patel, G. Jensen, A. Bhirde, J. D. Gong, S. N. Kim, J. Gillespie, J. S. Gutkind, F. Papadimitrakopoulos, J. F. Rusling, Carbon nanotube amplification strategies for highly sensitive immunodetection of cancer biomarkers. J. Am. Chem. Soc.,2006,128 (34), 11199-11205.
[8]R. D. Miller, In search of low-k dielectrics. Science,1999,286 (5439),421-423.
[9]T. Yamata, H. S. Zhou, D. Hiroishi, M. Tomita, Y. Ueno, K. Asai, I. Honma, Platinum surface modification of SBA-15 by y-radiation treatment. Adv. Mater.,2003,15 (6),511-513.
[10]M. E. Davis, Ordered porous materials for emerging applications. Nature,2002,417, 813-821.
[11]J. Kim, J. E. Lee, J. Lee, J. H. Yu, B. C. Kim, K. An, Y. Hwang, C. H. Shin, J. G. Park, J. Kim, T. Hyeon, Magnetic fluorescent delivery vehicle using uniform mesoporous silica spheres embedded with monodisperse magnetic and semiconductor nanocrystals. J. Am. Chem. Soc.,2006, 128 (3),688-689.
[12]X. Feng, G. E. Fryxell, L. Q. Wang, A. Y. Kim, J. Liu, K. M. Kemner, Functionalized monolayers on ordered mesoporous supports. Science,1997,276 (5314),923-926.
[13]B. W. Park, D. Y. Yoon, D. S. Kim, Recent progress in bio-sensing technique with encapsulated enzymes. Biosens. Bioelectron.,2010,26 (1),1-10.
[14]J. F. Parker, C. A. Fields-Zinna, R. W. Murray, The story of a monodisperse gold nanoparticle:Au25Llg. Acc. Chem. Res.,2010,43 (9),1289-1296.
[15]X. L. Ren, X. W. Meng, F. Q. Tang, L. Zhan, Biosensor enhanced by glucose oxidase biomimetic membrane containing the platinum and silica nanoparticles. Mater. Sci. Eng. C.,2009, 29,2234-2238.
[16]C. X. Lei, F. C. Gong, G. L. Shen, R. Q. Yu, Amperometric immunosensor for schistosoma japonicum antigen using antibodies loaded on a nano-Au monolayer modified chitosan-entrapped carbon paste electrode. Sens. Actuators, B,2003,96 (3),582-588.
[17]R. Yang, C. M. Ruan, W. L. Dai, J. Q. Deng, J. L. Kong, Electropolymerization of thionone in neutral aqueous media and H2O2 biosensor based on poly(thionine). Electrochim. Acta,1999, 44(10),1585-1596.
[18]F. N. Xia, D. B. Farmer, Y. M. Lin, P. Avouris, Graphene field-effect transistors with high on/off current ratio and large transport band gap at room temperature. Nano Lett.,2010,10 (2), 715-718.
[19]J. C. Meyer, A. K. Geim, M. I. Katsnelson, K. S. Novoselov, T. J. Booth, S. Roth, The structure of suspended graphene sheets. Nature,2007,446,60-63.
[20]J. H. Rouse, P. T. Lillehei, Electrostatic assembly of polymer/single walled carbon nanotube multilayer films. Nano Lett.,2003,3 (1),59-62.
[21]K. P. Liu, J. J. Zhang, C. M. Wang, J. J. Zhu, Graphene-assisted dual amplification strategy for the fabrication of sensitive amperometric immunosensor. Biosens. Bioelectron.,2011,26 (8), 3625-3632.
[22]C. J. Smith, P. C. Kelleher, Alpha-fetoprotein molecular heterogeneity. Physiologic correlations with normal growth, carcinogenesis and tumor growth. Biochim. Biophys. Acta,1980, 605 (1),1-32.
[23]H. Yokoo, T. Kondo, K. Fujii, T. Yamada, S. Todo, S. Hirohashi, Proteomic signature corresponding to alpha fetoprotein expression in liver cancer cells. Hepatology,2004,40 (3), 609-617.
[24]J. R. Gillespie, V. N. Uversky, Structure and function of a-fetoprotein:a biophysical overview. Biochim. Biophys. Acta,2000,1480 (1-2),41-56.
[25]J. J. Lu, S. Q. Liu, S. G. Ge, M. Yan, J. H. Yu, X. T. Hu, Ultrasensitive electrochemical immunosensor based on Au nanoparticles dotted carbon nanotube-graphene composite and functionalized mesoporous materials. Biosens. Bioelectron.,2012,33(1),29-35.
[26]Y. X. Fang, S. J. Guo, C. Z. Zhu, Y. M. Zhai, E. K. Wang, Self-assembly of cationic polyelectrolyte-functionalized graphene nanosheets and gold nanoparticles:a two-dimensional heterostructure for hydrogen peroxide sensing. Langmuir,2010,26 (13),11277-11282.
[27]S. Y. Wang, D. S. Yu, L. M. Dai, D. W. Chang, J. B. Baek, Polyelectrolyte-functionalized graphene as metal free electrocatalysts for oxygen reduction, ACS Nano,2011,5 (8),6202-6209.
[28]B. T. T. Nguyen, G. Koh, H. S. Lim, A. J. S. Chua, M. M. L. Ng, C. S. Toh, Membranebased electrochemical nanobiosensor for the detection of virus. Anal. Chem.,2009,81 (17),7226-7234.
[29]K. Kerman, N. Nagatani, M. Chikae, T. Yuhi, Y. Takamura, E. Tamiya, Labelfree electrochemical immunoassay for the detection of human chorionic gonadotropin hormone. Anal. Chem.,2006,78(15),5612-5616.