生物抗氧化剂电化学传感器检测技术
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摘要
人体及食品中的氧化反应是人们广泛关注的研究课题,氧化代谢产生的能量对于细胞的存活具有十分重要的意义,但是氧化过程会产生一系列的氧化自由基。如果生物体内产生过量的自由基,打破自由基与抗氧化剂的平衡,那么自由基的破坏能力就会超过体内抗氧化剂(如超氧化物歧化酶、过氧化氢酶、过氧化物酶等等)的保护能力并且会通过氧化细胞膜、损伤DNA或者酶等阻碍细胞本身的自我修复功能,导致生物大分子功能和结构损伤、细胞破坏、凋亡或死亡。在食品科学领域,这种氧化反应也会引起食物变质(如营养价值、颜色、气味、质地以及食品安全性的改变),据统计,世界上大约有一半的水果蔬菜存放期间发生腐败变质反应。因此,建立快速、有效的抗氧化剂分析方法对于生命科学和食品科学分析具有很好的理论和应用研究价值。本文具体工作如下:
1. Fe-DTPA,血红素,血红蛋白/TiO_2纳米颗粒修饰的抗氧化剂传感器检测技术首先将铟锡氧化物玻璃用二氧化钛纳米颗粒涂覆好,然后用来吸附含铁化合物或蛋白质。当加负电位的时候电极表面的溶解氧就会还原成过氧化氢,体系中产生的过氧化氢又可以将Fe~(Ⅱ)氧化成Fe~(Ⅲ),继而Fe~(Ⅲ)的电化学还原就会使催化电流增加。在抗氧化剂存在的情况下,过氧化氢被淬灭,催化电流就会减小,电流的减小程度与抗氧化剂的量呈正比关系。并且提出了抗氧化剂对过氧化氢清除能力的动力学模型。这种电极的使用使得抗氧化剂检测变得非常简单:将传感器浸入样品溶液(空气饱和的溶液就可以),进行阴极极化扫描,读出抗氧化能力的值就可以了。本研究工作可以作为以前基于羟基自由基和超氧阴离子自由基清除能力检测的一种补充方法,但是这种传感器非常易于制造和使用。
2.羟基自由基在DNA上传递距离的研究基于DNA的电子传递原理,制备了可受磁场调节的ds-DNA-Fe_3O_4@TiO_2电极。首先制备好巯基DNA修饰电极,然后将目标DNA末端的氨基进行氨羧络合反应,接着进行DNA杂交反应,当加入嵌入剂AQMS或MB时,用方波伏安法检测,得到AQMS或MB嵌入DNA双链的经典图形,说明DNA双链形成。最后再将杂交完成的ds-DNA与磁性纳米颗粒结合起来,当用紫外照射的时候,产生的羟基自由基就会损伤DNA。为研究羟基自由基在DNA上的传递距离,加上外界磁场进行调节,观察磁场对不同长度的DNA受紫外照射损伤的调节情况,巧妙地运用DNA的双链部分作为参照,以DNA的单链部分作为羟基自由基在DNA单链上传递距离的标尺,计算了羟基自由基在DNA上的扩散作用距离。
Oxidation in vivo or in the diet has aroused widespread concern.Oxidative metabolism is of great importance for the survival of cell. But also has its negative side, side effect is it can led to oxidant caused by free radicals or other reactive oxidant species, which produced during the metabolism process. More and more evidence can prove that, these species are able to form a control mechanism in a variety of organisms. The destructive power of excess radicals usually exceed protection mechanisms(such as superoxide dismutase, catalase, peroxidase, etc.) and will prevent self-healing capabilities of cell through oxidant membrane or damage DNA, eventually lead to cell damage or death (eg apoptosis).However, the mechanism of the reactive oxygen species has not yet been solved. The oxidation reaction is one of the factors, which causing food spoilage(such as changes in the nutritional value, color, odor, texture, as well as food safety). It is estimated that, there are about half of the fruits and vegetables spoiled due to expired harvest time. Thus,it is very necessary to establish a good defense mechanism and an efficient method to detect it. The main works are as follows:
1. Antioxidant Sensors Based on Iron Diethylenetriaminepentaacetic Acid, Hematin, and Hemoglobin Modified TiO2 Nanoparticle Printed Electrodes
Antioxidant amperometric sensors based on iron-containing complexes and protein modified electrodes were developed. Indium tin oxide glass was printed with TiO_2 nanoparticles, onto which iron-containing compounds and protein were adsorbed. When applied with negative potentials, the dissolved oxygen is reduced to H_2O_2 at the electrode surface, and the H_2O_2 generated in situ oxidizes Fe~(II) to Fe~(III), and then electrochemical reduction of Fe~(III) therefore gives rise to a catalytic current. In the presence of antioxidants, H_2O_2 was scavenged, the catalytic current was reduced, and the decreased current signal was proportional to the quantity of existing antioxidants. A kinetic model was proposed to quantify the H_2O_2 scavenging capacities of the antioxidants. With the use of the sensor developed here, antioxidant measurements can be done quite simply: put the sensor into the sample solutions (in aerobic atmosphere), perform a cathodic polarization scan, and then read the antioxidant activity values. The present work can be complementary to the previous studies of antioxidant sensor techniques based on OH radicals and superoxide ions scavenging methods, but the sensor developed here is much easier to fabricate and use.
2. How far can hydroxl radical translate on DNA helix?
Based on the principles of DNA charge transfer, we made a kind of electrode that can be regulated by the magnetic field, which was denoted as ds-DNA-Fe_3O_4@TiO_2. First prepare SH-DNA modified electrode, then prepare target DNA (with amino on the terminal)solution ,and carry on amino-carboxyl complex reaction. In order to remove DNA which is non-specific adsorpted on the electrode surface ,put the SH-DNA modified electrode in to MCH solution for a period of time. When perform hybridization reaction, add intercalator AQMS or MB, then test with OSW voltammograms. Put the electrode under Uv illumination, OH radicals produced during this process will damage DNA. In order to study the transmission distance of hydroxyl radical on DNA , we add a magnet to adjust the level of DNA damage.
1. Fe-DTPA,血红素,血红蛋白/TiO_2纳米颗粒修饰的抗氧化剂传感器检测技术首先将铟锡氧化物玻璃用二氧化钛纳米颗粒涂覆好,然后用来吸附含铁化合物或蛋白质。当加负电位的时候电极表面的溶解氧就会还原成过氧化氢,体系中产生的过氧化氢又可以将Fe~(Ⅱ)氧化成Fe~(Ⅲ),继而Fe~(Ⅲ)的电化学还原就会使催化电流增加。在抗氧化剂存在的情况下,过氧化氢被淬灭,催化电流就会减小,电流的减小程度与抗氧化剂的量呈正比关系。并且提出了抗氧化剂对过氧化氢清除能力的动力学模型。这种电极的使用使得抗氧化剂检测变得非常简单:将传感器浸入样品溶液(空气饱和的溶液就可以),进行阴极极化扫描,读出抗氧化能力的值就可以了。本研究工作可以作为以前基于羟基自由基和超氧阴离子自由基清除能力检测的一种补充方法,但是这种传感器非常易于制造和使用。
2.羟基自由基在DNA上传递距离的研究基于DNA的电子传递原理,制备了可受磁场调节的ds-DNA-Fe_3O_4@TiO_2电极。首先制备好巯基DNA修饰电极,然后将目标DNA末端的氨基进行氨羧络合反应,接着进行DNA杂交反应,当加入嵌入剂AQMS或MB时,用方波伏安法检测,得到AQMS或MB嵌入DNA双链的经典图形,说明DNA双链形成。最后再将杂交完成的ds-DNA与磁性纳米颗粒结合起来,当用紫外照射的时候,产生的羟基自由基就会损伤DNA。为研究羟基自由基在DNA上的传递距离,加上外界磁场进行调节,观察磁场对不同长度的DNA受紫外照射损伤的调节情况,巧妙地运用DNA的双链部分作为参照,以DNA的单链部分作为羟基自由基在DNA单链上传递距离的标尺,计算了羟基自由基在DNA上的扩散作用距离。
Oxidation in vivo or in the diet has aroused widespread concern.Oxidative metabolism is of great importance for the survival of cell. But also has its negative side, side effect is it can led to oxidant caused by free radicals or other reactive oxidant species, which produced during the metabolism process. More and more evidence can prove that, these species are able to form a control mechanism in a variety of organisms. The destructive power of excess radicals usually exceed protection mechanisms(such as superoxide dismutase, catalase, peroxidase, etc.) and will prevent self-healing capabilities of cell through oxidant membrane or damage DNA, eventually lead to cell damage or death (eg apoptosis).However, the mechanism of the reactive oxygen species has not yet been solved. The oxidation reaction is one of the factors, which causing food spoilage(such as changes in the nutritional value, color, odor, texture, as well as food safety). It is estimated that, there are about half of the fruits and vegetables spoiled due to expired harvest time. Thus,it is very necessary to establish a good defense mechanism and an efficient method to detect it. The main works are as follows:
1. Antioxidant Sensors Based on Iron Diethylenetriaminepentaacetic Acid, Hematin, and Hemoglobin Modified TiO2 Nanoparticle Printed Electrodes
Antioxidant amperometric sensors based on iron-containing complexes and protein modified electrodes were developed. Indium tin oxide glass was printed with TiO_2 nanoparticles, onto which iron-containing compounds and protein were adsorbed. When applied with negative potentials, the dissolved oxygen is reduced to H_2O_2 at the electrode surface, and the H_2O_2 generated in situ oxidizes Fe~(II) to Fe~(III), and then electrochemical reduction of Fe~(III) therefore gives rise to a catalytic current. In the presence of antioxidants, H_2O_2 was scavenged, the catalytic current was reduced, and the decreased current signal was proportional to the quantity of existing antioxidants. A kinetic model was proposed to quantify the H_2O_2 scavenging capacities of the antioxidants. With the use of the sensor developed here, antioxidant measurements can be done quite simply: put the sensor into the sample solutions (in aerobic atmosphere), perform a cathodic polarization scan, and then read the antioxidant activity values. The present work can be complementary to the previous studies of antioxidant sensor techniques based on OH radicals and superoxide ions scavenging methods, but the sensor developed here is much easier to fabricate and use.
2. How far can hydroxl radical translate on DNA helix?
Based on the principles of DNA charge transfer, we made a kind of electrode that can be regulated by the magnetic field, which was denoted as ds-DNA-Fe_3O_4@TiO_2. First prepare SH-DNA modified electrode, then prepare target DNA (with amino on the terminal)solution ,and carry on amino-carboxyl complex reaction. In order to remove DNA which is non-specific adsorpted on the electrode surface ,put the SH-DNA modified electrode in to MCH solution for a period of time. When perform hybridization reaction, add intercalator AQMS or MB, then test with OSW voltammograms. Put the electrode under Uv illumination, OH radicals produced during this process will damage DNA. In order to study the transmission distance of hydroxyl radical on DNA , we add a magnet to adjust the level of DNA damage.
引文
[1] Gerschman, R., Gilbert, D. L., et al. Oxygen poisoning and x-irradiation—A mechanism incommon. Science, 1954,119, 623–626.
[2] Commoner, B., Townsend, J., Pake, G. E. Free radicals in biological materials. Nature, 1954,174, 689–691.
[3] Harman, D. Aging—A theory based on free-radical and radiation-chemistry. J. Gerontol., 1956, 11, 298–300.
[4] McCord, J. M., Fridovich, I. Superoxide dismutase an enzymic function for erythrocuprein Hemocuprein. J. Biol. Chem., 1969,244, 6049–6055.
[5] Mittal, C. K., Murad, F. Activation of guanylate cyclase by superoxide-dismutase and hydroxyl radical—Physiological regulator of guanosine 3,5-monophosphate formation. Proc. Natl. Acad. Sci. U.S.A., 1977, 74, 4360–4364.
[6] B. Prieto-Sim′on, M. Cortina, M. Camp`as, et al. Electrochemical biosensors as a tool for antioxidant capacity assessment ,Sensors and Actuators B ,2008, 129,459–466.
[7] Valko, M., Rhodes, C. J., Moncol, et al. Free radicals, metals and antioxidants in oxidative stress-induced cancer. Chem. Biol. Interact., 2006, 160, 1–40.
[8] Valko , Dieter Leibfritz, Jan Moncola, et al. Free radicals and antioxidants in normal physiological functions and human disease Marian The International Journal of Biochemistry & Cell Biology 2007, 39,44–84.
[9] Kovacic, P., Jacintho, J. D. Mechanisms of carcinogenesis: Focus on oxidative stress and electron transfer. Curr. Med. Chem., 2001, 8, 773–796.
[10] Ridnour, L. A., Isenberg, J. S., Espey, M. G., et al. Nitric oxide regulates angiogenesis through a functional switch involving thrombospondin-1. Proc. Natl. Acad. Sci. U.S.A., 2005, 102, 13147–13152.
[11] Valko, M., Morris, et al. Oxygen free radical generating mechanisms in the colon: Do the semiquinones of Vitamin K play a role in the aetiology of colon cancer? Biochim. Biophys. Acta, 2001,1527, 161–166.
[12] Dr¨oge, W. Free radicals in the physiological control of cell function. Physiol. Rev., 2002, 82, 47–95.
[13] Halliwell, B., Gutteridge, J. M. C. Free radicals in biology and medicine (3rd ed.). 1999,Oxford University Press.
[14] Miller, D. M., Buettner, G. R., Aust, S. D. Transition metals as catalysts of“autoxidation”reactions. Free Radic. Biol. Med., 1990, 8, 95–108.
[15] Valko, M.,Morris, H., Cronin, M. T. D. Metals, toxicity and oxidative stress. Curr. Med. Chem., 2005,12, 1161–1208.
[16] Cadenas, E., Sies, H. The lag phase. Free. Radic. Res., 1998,28, 601–609.
[17] Kovacic, P., Pozos, R. S., et al. Mechanism of mitochondrial uncouplers, inhibitors, and toxins: Focus on electron transfer, free radicals, and structure–activity relationships. Curr. Med. Chem., 2005,12, 2601–2623.
[18] Valko, M., Izakovic, M., Mazur, et al. Role of oxygen radicals in DNA damage and cancer incidence. Mol. Cell. Biochem., 2004,266, 37–56.
[19] Pastor, N., Weinstein, H., et al. A detailed interpretation of OH radical footprints in a TBP DNA complex reveals the role of dynamics in the mechanism of sequence specific binding. J. Mol. Biol., 2000,304, 55–68.
[20] Liochev, S. I., Fridovich, I. The role of O2 in the production of HO: In vitro and in vivo. Free Radic. Biol. Med., 1994, 16, 29–33.
[21] Liochev, S. I., Fridovich, I. The Haber–Weiss cycle—70 years later: An alternative view. Redox Rep., 2002, 7, 55–57.
[22] De Grey, A. D. N. J. HO2?: The forgotten radical. DNA Cell Biol., 2002, 21, 251–257.
[23] Aikens, J.,Dix, T. A. Perhydroxyl radical (HOO?) Initiated lipid-peroxidation—The role of fatty-acid hydroperoxides. J. Biol. Chem., 1991,266, 15091–15098.
[24] Borges, F., Fernandes, E., et al. Progress towards the discovery of xanthine oxidase inhibitors. Curr. Med. Chem., 2002, 9, 195–217.
[25] Vorbach, C., Harrison, R., Capecchi, et al. Xanthine oxidoreductase is central to the evolution and function of the innate immune system. Trends Immunol., 2003,24, 512–517.
[26] Valko, M., Izakovic, M., et al. Role of oxygen radicals in DNA damage and cancer incidence. Mol. Cell. Biochem., 2004,266, 37–56.
[27] Ghafourifar, P., Cadenas, E. Mitochondrial nitric oxide synthase. Trends Pharmacol. Sci., 2005, 26, 190–195.
[28] Bergendi, L., Benes, L., Durackova, et al. Chemistry, physiology and pathology of free radicals. Life Sci., 1999, 65, 1865–1874.
[29] Koshland, D. E. The molecule of the year. Science, 1992,258, 1861.
[30] Chiueh, C. C. Neuroprotective properties of nitric oxide. Ann. N.Y. Acad. Sci., 1999, 890, 301–311.
[31] Klatt, P., Lamas, et al. Regulation of protein function by Sglutathiolation in response to oxidative and nitrosative stress. Eur. J. Biochem., 2000,267, 4928–4944.
[32] Ridnour, L. A., Thomas, D. D., et al. The chemistry of nitrosative stress induced by nitric oxide and reactive nitrogen oxide species. Putting perspective on stressful biological situations. Biol. Chem., 2004,385, 1–10.
[33] Carr, A.,McCall, et al.Oxidation of LDL by myeloperoxidase and reactive nitrogen species-reaction pathways and antioxidant protection. Arterioscl. Thromb. Vasc. Biol., 2000,20, 1716–1723.
[34] Valko, M., Rhodes, et al. Free radicals, metals and antioxidants in oxidative stress-induced cancer. Chem. Biol. Interact., 2006,160, 1–40.
[35] Halliwell, B., Gutteridge, et al. Free radicals in biology and medicine (3rd ed.). 1999 OxfordUniversity Press.
[36] Siems, W. G., Grune, et al. 4-Hydroxynonenal formation during ischemia and reperfusion of rat small-intestine. Life Sci., 1995, 57, 785–789.
[37] Stadtman, E. R. Role of oxidant species in aging. Curr. Med. Chem., 2004, 11, 1105–1112.
[38]“antioxidant”. Webster’s Third New International Dictionary, Unabridged; Merriam-Webster: 2002.
[39] Halliwell, B. How to characterize a biological antioxidant. Free Radical Res. Commun. 1990, 9, 1-32.
[40] Cadenas, E. Basic mechanisms of antioxidant activity. Biofactors, 1997, 6, 391–397.
[41] Masella, R., Di Benedetto, et al. Novel mechanisms of natural antioxidant compounds inbiological systems: Involvement of glutathione and glutathionerelated enzymes. J. Nutr. Biochem., 2005, 16, 577–586.
[42] Shen, D., Dalton, T. P., et al.Glutathione redox state regulates mitochondrial reactive oxygen production. J. Biol. Chem., 2005, 280, 25305–25312.
[43] Nogueira, C. W., Zeni, et al. Organoselenium and organotellurium compounds: Toxicology and pharmacology. Chem. Rev., 2004, 104, 6255–6285.
[44]Agamey, A., Lowe, G. M., et al. Carotenoid radical chemistry and antioxidant/pro-oxidant properties. Arch. Biochem. Biophys., 2004, 430, 37–48.
[45]Kojo, S. Vitamin C: Basic metabolism and its function as an index of oxidative stress. Curr. Med. Chem., 2004,11, 1041–1064.
[46] Landis, G. N.,Tower, J. Superoxide dismutase evolution and life span regulation. Mech. Ageing Dev., 2005,126, 365–379.
[47] Miller, E. R., Pastor-Barriuso, et al. Meta-analysis: High-dosage Vitamin E supplementation may increase all-cause mortality. Ann. Intern. Med., 2005,142, 37–46.
[48] Schrauzer, G. N. Interactive effects of selenium and chromium on mammary tumor development and growth in MMTV-infected female mice and their relevance to human cancer. Biol. Trace Element Res., 2006,109, 281–292.
[49] Sharoni, Y., Danilenko, et al. Carotenoids and transcription. Arch. Biochem. Biophys., 2004 430, 89–96.
[50] Smith, A. R., Shenvi, et al. Lipoic acid as a potential therapy for chronic diseases associated with oxidative stress. Curr. Med. Chem., 2004,11, 1135–1146.
[51] Lucarini, M.; Pedrielli, et al. Bond dissociation energies of the N-H bond and rate constants for the reaction with alkyl, alkoxyl, and peroxyl radicals of phenothiazines and related compounds. J. Am. Chem. Soc. 1999, 121, 11546-11553.
[52] Wright, J. S.,Johnson, E. R.; et al. Predicting the activity of phenolic antioxidants: theoretical method, analysis of substituent effects, and application to major families of antioxidants. J. Am. Chem. Soc. 2001, 123, 1173-1183.
[53]Quick, K. L., Hardt, et al. Rapid microplate assay for superoxide scavenging efficiency. J. Neurosci. Methods 2000, 97, 138-144.
[54]Yamashita, N., Murata, M., Inoue, S.,et al. R-Tocopherol induces oxidative damage to DNA in the presence of copper(II) ions. Chem. Res. Toxicol. 1998, 11, 855-862.
[55] Ewing, J. F.; Janero, D. R. Microplate superoxide dismutase assay employing nonenzymatic superoxide generator. Anal. Biochem. 1995, 232, 243-248.
[56] Cotton, F. A.; Wilkinson, G.; Murillo, C. A.; et al. AdVances in Inorganic Chemistry, 6th ed.; Wiley: New York, 1999; 451 .
[57] Zhao, H.; Kalivendi, S.; Zhang, H.; et al. Superoxide reacts with hydroethidine but forms a fluorescent product that is distinctly different from ethidium: potential implications in intracellular fluorescence detection of superoxide. Free Radical Biol. Med. 2003, 34, 1359-1368.
[58] Martinez-Tome, M.; Garcia-Carmona, F.; Murcia, M. A. Comparison of the antioxidants and pro-oxidants activities of broccoli amino acids with those of common food additives. J. Sci. Food Agric. 2001, 81, 1019-1026.
[59] Zhu, B. Z.; Kitrosky, N.; Chevion, M. Evidence for production of hydroxyl radicals by pentachlorophenol metabolites and hydrogen peroxide: A metal-independent organic Fenton reaction. Biochem. Biophys. Res. Commun. 2000, 270 (3), 942-946.
[60] Halliwell, B. Antioxidant characterization, methodology and mechanism. Biochem. Pharmacol. 1995, 49, 1341.
[61] Ou, B.; Hampsch-Woodill, M.; Flanagan, J.; et al. Novel fluorometric assay for hydroxyl radical prevention capacity using fluorescein as the probe. J. Agric. Food Chem. 2002, 50, 2772-2777.
[62] Sies, H.; Stahl, W. Carotenoids and UV protection. Photochem. Photobiol. Sci. 2004, 3 (8), 749-752.
[63] Zigman, S. Lens UVA photobiology. J. Ocul. Pharmocol. Ther. 2000, 16 (2), 161-165.
[64] Rozanowska, M.; Wessels, J.; Boulton, M.; et al. Blue light-induced singlet oxygen generation by retinal lipofuscin in non-polar media. Free Radical Biol. Med. 1998, 24, 1107-1112.
[65] Ebermann, R.; Alth, G.; Kreitner, M.; et al. Natural products derived from plants as potential drugs for the photodynamic destruction of tumor cells. J. Photochem. Photobiol. B 1996, 36, 95-97.
[66] Tarr, M.; Velenzeno, D. P. Singlet oxygen: the relevance of extracellular production mechanisms to oxidative stress in ViVo. Photochem. Photobiol. Sci. 2003, 2, 355-361.
[67] Martinez, G. R.; Ravanat, J. L.; Medeiros, M. H. G.; et al. Synthesis of a naphthalene endoperoxide as a source of O-18-labeled singlet oxygen for mechanistic studies. J. Am. Chem. Soc. 2000, 122, 10212-10213.
[68] Busby, R. H. M.; Hamblett, C. G. I.; Gorman, A. A. Quenching of singlet oxygen by Trolox C, ascorbate, and amino acids effects of pH and temperature. J. Phys. Chem. A 1999, 103, 7454-7459.
[69] Wilkinson, F.; Helman, W. P.; Ross, A. B. Rate constants for the decay and reactions of the lowest electronically excited singlet state of molecular oxygen in solution. An expanded and revised compilation. J. Phys. Chem. Ref. Data 1995, 24, 663-1021.
[70] Fu, Y. L.; Krasnovsky, A. A.; Foote, C. S. Quenching of singlet oxygen and sensitized delayed phthalocyanine fluorescence. J. Phys. Chem. A 1997, 101, 2552-2554.
[71] Moncada, S.; Higgs, E. A. Molecular mechanisms and therapeutic strategies related to NO. FASEB J. 1995, 9, 1319.
[72] Pryor, W. A.; Squadrito, G. L. The chemistry of peroxynitrite: a product from the reaction of NO and O2 . Am. J. Physiol. 1995, 268, L699.
[73] Squadrito, G. L.; Pryor, W. A. Mapping the reaction of peroxynitrite with CO2: energetics, reactive species, and biological implications. Chem. Res. Toxicol. 2002, 15, 885-895.
[74] Pannala, A.; Razaq, R.; Halliwell, B.; et al. Inhibition of peroxynitrite dependent tyrosine nitration by hydroxycinnamates: Nitration or electron donation? Free Radical Biol. Med. 1998, 24, 594-606.
[75] Kooy, N. W. R.; J. A.; Ischiropoulos, H.; et al. Peroxynitrite-mediated oxidation of dihydrorhodamine 123. Free Radical Biol. Med. 1994, 20, 149-156.
[76] Paquay, J. B. G.; Haenen, G. R. M. M.; Stender, G.; et al. Protection against nitric oxide toxicity by tea. J. Agric. Food Chem. 2000, 48, 5768-5772.
[77] Harman, D., Aging-A theory based on free-radical and radiation-chemistry. J. Gerontol., 1956. 11, 298-300.
[78] Valko, M., et al., Free radicals and antioxidants in normal physiological functions and human disease. Intern. J. Biochem. Cell Biol., 2007,39, 44-84.
[79] Halliwell, B., Free radicals, antioxidants and human disease : curiosity, cause, or consequence ? Lancet, 1994, 344: 721-724.
[80] Evans, M.D. and M.S. Cooke, Factors contributing to the outcome of oxidative damage to nucleic acids. BioEssays, 2004,26(5): 533-542.
[81] Valko, M., H. Morris, et al. Metals, toxicity and oxidative stress. Curr. Med. Chem., 2005. 12,1161-1208.
[82] Aust, A.E. and J.F. Eveleigh, Mechanisms of DNA Oxidation. Proc. Soc. Exp. Biol. Med., 1999. 222,246-252.
[83] Fojta, M., et al., Electrode potential-controlled DNA damage in the presence of copper ions and their complexes. Bioelectrochem., 2002. 55, 25-27.
[84] Palecek, E., et al., Electrochemical biosensors for DNA hybridization and DNA damage. Biosens. Bioelectron., 1998. 13,621-628.
[85] Labuda, J., et al., Detection of antioxidative activity of plant extracts at the DNA-modified screen-printed electrode. Sensors, 2002. 2(1), 1-10.
[86] White, B., et al., Oscillating Formation of 8-Oxoguanine during DNA Oxidation. J. Am. Chem. Soc., 2003, 125,6604-6605.
[87] Fojta, M., T. Kubicarova, and E. Palecek, Electrode potential-modulated cleavage of surface-confined DNA by hydroxyl radicals detected by an electrochemical biosensor. Biosens. Bioelectron., 2000. 15, 107-115.
[88] Cadenas, E., Basic mechanisms of antioxidant activity. Biofactors, 1997. 6,391-397.
[89] McCord, J.M. and I. Fridovich, Superoxide dismutase an enzymic function for erythrocuprein Hemocuprein. J. Biol. Chem., 1969. 244,6049-6055.
[90] Chance, B., H. Sies, and A. Boveris, Hydroperoxide metabolism in mammalian organs. Physiol. Rev., 1979. 59,527-605.
[91] Maiorino, M., et al., Phospholipid hydroperoxide glutathione peroxidase is the 18 kDa selenoprotein expressed in human tumor cell lines. J. Biol. Chem., 1991. 266,7728-7732.
[92] Huang, D., B. Ou, et al. The Chemistry behind Antioxidant Capacity Assays. J. Agric. Food Chem., 2005. 53,1841-1856.
[93] Antolovich, M., et al., Methods for testing antioxidant activity. Analyst, 2002, 127,183-198.
[94] Wayner, D.D.M., et al., Quantitative measurement of the total, per oxyl radical-trapping antioxidant capability of human blood plasma by controlled peroxidation. FEBS Lett., 1985,187,33-37.
[95] Cao, G.H., H.M. et al. Oxygen-radical absorbency capacity assay for antioxidants. Free Radical Biol.Med., 1993, 14,303-311.
[96] Miller, N.J., et al., A Novel method for measuring antioxidant capacity and its application to monitoring antioxidant status in premature neonates. Clin. Sci., 1993, 84, 407-412.
[97] Benzie, I.F.F. and J.J. Strain, The ferric reducing ability of plasma as a measure of antioxidant power the FRAP assay,. Anal. Biochem., 1996, 239:70-76.
[98] Blois, M.S., Antioxidant determinations by the use of a stable free radical. Nature, 1958, 181: 1199-1200.
[99] Korotkova, E.I., Y.A. Karbainov, et al. Investigation of antioxidant and catalytic properties of some biologically active substances by voltammetry. Anal. Bioanal. Chem., 2003, 375: 465-468.
[100] Bukova, M., et al., Detection of damage to DNA and antioxidative activity of yeast polysaccharides at the DNA-modified screen-printed electrode. Talanta, 2002, 56: 939-947.
[101] Liu, J., et al., Antioxidant Sensors Based on DNA-Modified Electrodes. Anal. Chem., 2005, 77(23): 7687-7694.
[102] Liu, J., et al., Generation of OH radicals at palladium oxide nanoparticle modified electrodes, and scavenging by fluorescent probes and antioxidants. J. Electroanal. Chem., 2008,619-620: 131-136.
[103] Campanella, L., et al., Determination of antioxidant properties of aromatic herbs,olives and fresh fruit using an enzymatic sensor. . Anal. Bioanal. Chem., 2003, 375: 1011-1016.
[104] Campanella, L., E. Martini, and M. Tomassetti, Antioxidant capacity of the algae using a biosensor method. Talanta, 2005,66: 902-911.
[105] Campanella, L., A. Bonanni, and M. Tomassetti, Determination of the antioxidant capacity of samples of different types of tea, or of beverages based on tea or other herbal products, using a superoxide dismutase biosensor. J. Pharm. Biomed. Anal. , 2003, 32: 725-736.
[106] Campanella, L., et al., Biosensors for determination of total and natural antioxidant capacity of red and white wines: comparison with other spectrophotometric and fluorimetric methods. Biosens. Bioelectron., 2004, 19: 641-651.
[107] Campanella, L.,et al., Biosensors for determination of total antioxidant capacity ofphytotherapeutic integrators: comparison with other spectrophotometric, fluorimetric and voltammetric methods. J. Pharm. Biomed. Anal. , 2004, 35: 303-320
[108] Campanella, L., et al., Comparison of fluorimetric, voltammetric and biosensor methods for the determination of total antioxidant capacity of drug products containing acetylsalicylic acid., in J. Pharm. Biomed. Anal. 2004, 91-99.
[109] Campanella, L., et al., New biosensor for superoxide radical used to evidence molecules of biomedical and pharmaceutical interest having radical scavenging properties. J. Pharm. Biomed. Anal. , 2000, 23: 69-76.
[110] Korotkova, E.I., Y.A. Karbainov, and A.V. Shevchuk, Study of antioxidant properties by voltammetry. J. Electroanal. Chem., 2002,518: 56-60.
[111] Avramchik, O.A., et al., Antioxidant and electrochemical properties of calcium and lithium ascorbates. J. Pharm. Biomed. Anal., 2005,37: 1149-1154.
[112] Bashkatova, N.V., et al., Electrochemical, quantum-chemical and antioxidant properties of antipyrine and its derivatives. J. Pharm. Biomed. Anal., 2005, 37: 1143-1147.
[113] Korotkova, E.I., et al., Study of antioxidant properties of a water-soluble Vitamin E derivative-tocopherol monoglucoside (TMG) by differential pulse voltammetry. Talanta, 2004,63: 729-734.
[114] Kong, Y.-T., et al., Peroxidase-Based Amperometric Sensor for the Determination of Total Phenols Using Two-Stage Peroxidase Reactions. . Am. J. Enol. Vitic., 2001,52: 381-385.
[115] Prieto-Simon, B., et al., Electrochemical biosensors as a tool for antioxidant capacity assessment. Sens. Actuators, B, 2008, 129: 459-466.
[116] Fojta, M., et al., A supercoiled DNA-modified mercury electrode-based biosensor for the detection of DNA strand cleaving agents. Talanta, 1998,46: 155-161.
[117] Fojta, M. and E. Palecek, Supercoiled DNA-modified mercury electrode: A highly sensitive tool for the detection of DNA damage. Anal. Chim. Acta, 1997,342: 1-12.
[118] Palecek, E. and M. Fojta, Detecting DNA hybridization and damage. Anal. Chem., 2001, 73: 74A-83A.
[119] Fojta, M., L. Havran, and E. Palecek, Chronopotentiometric detection of DNA strand breaks with mercury electrodes modified with supercoiled DNA. Electroanalysis, 1997,9: 1033-1034.
[120] Mugweru, A. and J. Rusling, Studies of DNA Damage Inhibition by Dietary Antioxidants Using Metallopolyion/DNA Sensors. Electroanalysis, 2006,18: 327-332.
[121] Liu, J., et al., Anal. Chem., 2006,78: 6879-6884.
[122] Zhou, L., et al., Toxicity Screening by Electrochemical Detection of DNA Damage by Metabolites Generated In Situ in Ultrathin DNA-Enzyme Films. J. Am. Chem. Soc., 2003, 125(5): 1431-1436.
[123] Thorp, H.H., Cutting out the middleman: DNA biosensors based on electrochemical oxidation. Trends Biotechnol., 1998, 16(3): 117-121.
[124] Wang, B. and J.F. Rusling, Voltammetric Sensor for Chemical Toxicity Using[Ru(bpy)2poly(4-vinylpyridine)10Cl)]+ as Catalyst in Ultrathin Films. DNA Damage from Methylating Agents and an Enzyme-Generated Epoxide. Anal. Chem., 2003, 75(16): 4229-4235.
[125] Labuda, J., Anal. Bioanal. Chem. , 2009, 394: 855-861.
[126] Huang, M., et al., Alternate Assemblies of Platinum Nanoparticles and Metalloporphyrins as Tunable Electrocatalysts for Dioxygen Reduction. Langmuir, 2005, 21:323-329.
[127] Wang, B., et al., Sol?Gel Thin-Film Immobilized Soybean Peroxidase Biosensor for the Amperometric Determination of Hydrogen Peroxide in Acid Medium. Anal. Chem. , 1999, 71: 1935-1939.
[128] Zhang, G. and P.K. Dasgupta, Hematin as a peroxidase substitute in hydrogen peroxide determinations. . Anal. Chem., 1992, 64: 517-522.
[129] Zhou, H., et al., Hemoglobin-Based Hydrogen Peroxide Biosensor Tuned by the Photovoltaic Effect of Nano Titanium Dioxide. Anal. Chem. , 2005, 77: 6102-6104.
[130] Shi, C. and F.C. Anson, Inorg. Chem. , 1998,37: 1037-1043.
[131] Shen, Y., et al., Electroanalysis, 2002, 14: 1557- 1563.
[132] Shi, C. and F.C. Anson, Inorg. Chem., 1995, 34: 4554-4561.
[133]Finnen, D.C., et al., Structures and Spectroscopic Characteristics of Iron(II1) Diethylenetriaminepentaacetic Acid Complexes. A Non-Heme Iron(III) Complex with Relevance to the Iron Environment in Lipoxy genases. . Inorg. Chem., 1991,30: 3960-3964.
[134] Nazeeruddin, M. K., etal., Conversion of Light to Electricity by cis-XzBis( 2,2’-bipyridyl-4,4’-dicarboxylate)ruthenium( 11) Charge-Transfer Sensitizers (X = C1-, Br-, I-, CN-, and SCN-) on Nanocrystalline Ti02 Electrodes. J. Am. Chem. Soc., 1993, 115: 6382-6390.
[135] Meier, K.-R. and M. Gratzel, Redox targeting of oligonucleotides anchored to nanocrystalline TiO2 films for DNA detection. ChemPhysChem, 2002,3:371-374.
[136] Shinohara, H., et al., Bioelectrochem. Bioenerg. , 1991,26: 307-320.
[137] Topoglidis, E., et al., Protein Adsorption on Nanocrystalline TiO2 Films: An Immobilization Strategy for Bioanalytical Devices. Anal. Chem., 1998,70(23): 5111-5113.
[138] Topoglidis, E., et al., Protein adsorption on nanoporous: a novel approach TiO2 to studying photoinduced protein/electrode transfer reactions. Faraday Discuss., 2000, 116: 35-46.
[139] Rajh, T., et al., Surface Restructuring of Nanoparticles: An Efficient Route for Ligand-Metal Oxide Crosstalk. J. Phys. Chem. B 2002, 106: 10543-10552.
[140] Moser, J., et al., Surface Complexation of Colloidal Semiconductors Strongly Enhances Interfacial Electron-Transfer Rates. Langmuir, 1991, 7: 3012-3018.
[141] Ishibashi, K., et al., Detection of active oxidative species in TiO2 photocatalysis using the fluorescence technique. Electrochem. Commun., 2000, 2: 207-210.
[142] Ishibashi, K., et al., Quantum yields of active oxidative species formed on TiO2 photocatalyst. J. Photochem. Photobiol., A, 2000, 134: 139-142.
[143] Shen, Y., M. Trauble, and G. Wittstock, Detection of Hydrogen Peroxide Produced duringElectrochemical Oxygen Reduction Using Scanning Electrochemical Microscopy. Anal. Chem., 2008, 80: 750-759.
[144] Balbuena, P.B., et al., Adsorption and Dissociation of H2O2 on Pt and Pt-Alloy Clusters and Surfaces. J. Phys. Chem. B, 2006, 110: 17452-17459.
[145] Heyrovsky, M. and S. Vavricka, Heterogeneous electron transfer to molecular oxygen in aqueous solutions. J. Electroanal. Chem., 1992. 332: 309-313.
[146] Popovi?, T., et al., Synthesis and etructure of dehydro-4-iminoallantoin and its covealent adducts. Tetrahedron, 1991, 47: 317-322.
[147] Skinner, W.A. and P. Alaupovic, Oxidation Products of Vitamin E and Its Model, 6-Hydroxy-2,2,5,7,8-pentamethylchroman. V. Studies of the Products of Alkaline Ferricyanide Oxidation. J. Org. Chem. , 1963, 28: 2854-2858.
[148] Nanni, E.J., M.D. Stallings Jr., and D.T. Sawyer, Does Superoxide Ion Oxidize Catechol, a-Tocopherol, and Ascorbic Acid by Direct Electron Transfer? J. Am. Chem. Soc. , 1980, 102: 4481-4485.
[149] Thomas, M.J. and B.H.J. Bielskit, Oxidation and Reaction of Trolox c, a Tocopherol Analogue, in Aqueous Solution. A Pulse-Radiolysis Study. J. Am. Chem. Soc. , 1989, 111: 3315-3319.
[150] Priyadarsini, K.I., S. Kapoor, and D.B. Naik, One- and Two-Electron Oxidation Reactions of Trolox by Peroxynitrite. Chem. Res. Toxicol. , 2001,14: 567-571.
[151] Santos, C.X.C., E.I. Anjos, and O. Augusto, Uric Acid Oxidation by Peroxynitrite: Multiple Reactions, Free Radical Formation, and Amplification of Lipid Oxidation. Arch. Biochem. Biophy., 1999,372: 285-294.
[152] Ozgen, M., et al., Modified 2,2-Azino-bis-3-ethylbenzothiazoline-6-sulfonic Acid (ABTS) Method to Measure Antioxidant Capacity of Selected Small Fruits and Comparison to Ferric Reducing Antioxidant Power (FRAP) and 2,2‘-Diphenyl-1-picrylhydrazyl (DPPH) Methods. J. Agric. Food Chem., 2006,54: 1151-1157.
[153] K.-H. Yoo, D. H. Ha, J.-O Lee, et al. Choi, Electrical Conduction through Poly(dA)-Poly(dT) and Poly(dG)-Poly(dC) DNA Molecules. Phys. Rev. Lett. 2001, 87: 198102 (1-4).
[154] S. Delaney, J. K. Barton, Long-Range DNA Charge Transport, J. Org. Chem. 2003, 68, 6475-6483
[155] S. O. Kelley, J. K. Barton, Electrochemistry of Methylene Blue Bound to a DNA-Modified Electrode. Bioconjugate Chem. 1997, 8, 31-37.
[156] E. M. Boon, N. M. Jackson, M. D. Wightman, et al. Intercalative Stacking: A Critical Feature of DNA Charge-Transport Electrochemistry. J. Phys. Chem. B 2003, 107, 11805-11812.
[157] E. M. Boon, J.K. Barton, DNA Electrochemistry as a Probe of Base Pair Stacking in A-, B-,and Z-Form DNA. Bioconjugate Chem. 2003, 14, 1140-1147.
[158] A. K. Boal, J. K. Barton.Electrochemical Detection of Lesions in DNA. Bioconjugate Chem. 2005, 16, 312-321.
[159] S. O. Kelley, E. M. Boon, J. K. Barton, et al.Single-base mismatch detection based on charge transduction through DNA, Nucleic Acids Research, 1999, 27: 4830-4837.
[160] H.-W. Fink, C. Schonenberger. Electrical Conduction Through DNA Molecules. Nature 1999, 398:407-410.
[161] D. Porath, A. Bezryadin, S. de Vries, et al. Direct Measurement of Electrical Transport through DNA Molecules. Nature 2000, 403:635-638.
[162] E. L. S. Wong, J. Justin Gooding. The Electrochemical Monitoring of the Perturbation of Charge Transfer through DNA by Cisplatin. J. Am. Chem. Soc. 2007, 129: 8950-8951.
[163] Derfus, A. M., Chan, W. C. W., et al. Probing the cytotoxicity of semiconductor quantum dots. Nano Lett. 2004,4:11–18.
[164] P.R. Leroueil,S?. Hong,A. Mecke, ?et al. Holl.Nanoparticle Interaction with Biological Membranes. Acc. Chem. Res. 2007, 40, 335–342.
[165] Y. Jin, S. Kannan, M. Wu, et al. Toxicity of Luminescent Silica Nanoparticles to Living Cells. Anal. Chem., 2007, 79: 9150 -9159.
[166] J. A. Ryan, K. W. Overton, M. E. Speight, et al.Cellular Uptake of Gold Nanoparticles Passivated with BSA-SV40 Large T Antigen Conjugates. Nano Lett. 2006, 6: 1121-1125.
[167] A. Magrez, S. Kasas, V. Salicio, et al.Cellular Toxicity of Carbon-Based Nanomaterials. Langmuir, 2007, 23: 12783 -12787.
[168] N. Ma, J. Yang, K. M. Stewart, et al. DNA-Passivated CdS Nanocrystals: Luminescence, Bioimaging, and Toxicity Profiles. Nano Lett., 2007, 7: 3592 -3597.
[169] DNA Damage Induced by Multiwalled Carbon Nanotubes in Mouse Embryonic Stem Cells. L. Zhu, D. W. Chang, L. Dai, Y. Hong.
[170] Shik Chi Tsang, Chih Hao Yu,Xin Gao, Silica-Encapsulated Nanomagnetic Particle as a New Recoverable Biocatalyst Carrier ; J. Phys. Chem. B 2006, 110, 16914-16922.
[171] Elicia L. S. Wong and J. Justin Gooding;The Electrochemical Monitoring of the Perturbation of Charge Transfer through DNA by Cisplatin; J. AM. CHEM. SOC. 2007, 129, 8950-8951.
[172] Wong, E. L. S.; Gooding, J. J. Anal. Chem. 2006, 78, 2138.
[173] T. Rajh, L. X. Chen, K. Lukas, et al. Tiede;Surface Restructuring of Nanoparticles: An Efficient Route for Ligand-Metal Oxide Crosstalk; J. Phys. Chem. B 2002, 106, 10543-10552.
[174] Zeni, G. and R.C. Larock, Synthesis of heterocycles via palladium-catalyzed oxidation addition. Chem, Rev., 2006, 106: 4644-4680.
[175] Jifeng Liu, Christophe Roussel,Gre? goire Lagger, et al. Antioxidant Sensors Based on DNA-Modified Electrodes; Anal. Chem. 2005, 77, 7687-7694.
[176] Jeff Gore, Zev Bryant, Marcelo No¨llmann, et al.DNA overwinds when stretched Nature. 44217 August 2006.
[177] Bryant,Z. etal. Structural transitionsan delasticity from torque measurements on DNA. Nature 424, 2003.
[178] Smith,S.B.,Cui,Y.,Bustamante,C. Over stretching B-DNA: the elastic response of individual double-stranded and single-stranded DNA molecules. Science 271, 1996.
[179] Gore,J. Single-Molecule Studies of DNA Twist Mechanics and Gyrase Mechanochemistry. Thesis,Univ. California, Berkeley, 2005.
[180] Wang,M.D.,Yin,H.,etal.Stretching DNA with optical tweezers. Biophys.J. 72, 1335¨C-1346,1997.
[2] Commoner, B., Townsend, J., Pake, G. E. Free radicals in biological materials. Nature, 1954,174, 689–691.
[3] Harman, D. Aging—A theory based on free-radical and radiation-chemistry. J. Gerontol., 1956, 11, 298–300.
[4] McCord, J. M., Fridovich, I. Superoxide dismutase an enzymic function for erythrocuprein Hemocuprein. J. Biol. Chem., 1969,244, 6049–6055.
[5] Mittal, C. K., Murad, F. Activation of guanylate cyclase by superoxide-dismutase and hydroxyl radical—Physiological regulator of guanosine 3,5-monophosphate formation. Proc. Natl. Acad. Sci. U.S.A., 1977, 74, 4360–4364.
[6] B. Prieto-Sim′on, M. Cortina, M. Camp`as, et al. Electrochemical biosensors as a tool for antioxidant capacity assessment ,Sensors and Actuators B ,2008, 129,459–466.
[7] Valko, M., Rhodes, C. J., Moncol, et al. Free radicals, metals and antioxidants in oxidative stress-induced cancer. Chem. Biol. Interact., 2006, 160, 1–40.
[8] Valko , Dieter Leibfritz, Jan Moncola, et al. Free radicals and antioxidants in normal physiological functions and human disease Marian The International Journal of Biochemistry & Cell Biology 2007, 39,44–84.
[9] Kovacic, P., Jacintho, J. D. Mechanisms of carcinogenesis: Focus on oxidative stress and electron transfer. Curr. Med. Chem., 2001, 8, 773–796.
[10] Ridnour, L. A., Isenberg, J. S., Espey, M. G., et al. Nitric oxide regulates angiogenesis through a functional switch involving thrombospondin-1. Proc. Natl. Acad. Sci. U.S.A., 2005, 102, 13147–13152.
[11] Valko, M., Morris, et al. Oxygen free radical generating mechanisms in the colon: Do the semiquinones of Vitamin K play a role in the aetiology of colon cancer? Biochim. Biophys. Acta, 2001,1527, 161–166.
[12] Dr¨oge, W. Free radicals in the physiological control of cell function. Physiol. Rev., 2002, 82, 47–95.
[13] Halliwell, B., Gutteridge, J. M. C. Free radicals in biology and medicine (3rd ed.). 1999,Oxford University Press.
[14] Miller, D. M., Buettner, G. R., Aust, S. D. Transition metals as catalysts of“autoxidation”reactions. Free Radic. Biol. Med., 1990, 8, 95–108.
[15] Valko, M.,Morris, H., Cronin, M. T. D. Metals, toxicity and oxidative stress. Curr. Med. Chem., 2005,12, 1161–1208.
[16] Cadenas, E., Sies, H. The lag phase. Free. Radic. Res., 1998,28, 601–609.
[17] Kovacic, P., Pozos, R. S., et al. Mechanism of mitochondrial uncouplers, inhibitors, and toxins: Focus on electron transfer, free radicals, and structure–activity relationships. Curr. Med. Chem., 2005,12, 2601–2623.
[18] Valko, M., Izakovic, M., Mazur, et al. Role of oxygen radicals in DNA damage and cancer incidence. Mol. Cell. Biochem., 2004,266, 37–56.
[19] Pastor, N., Weinstein, H., et al. A detailed interpretation of OH radical footprints in a TBP DNA complex reveals the role of dynamics in the mechanism of sequence specific binding. J. Mol. Biol., 2000,304, 55–68.
[20] Liochev, S. I., Fridovich, I. The role of O2 in the production of HO: In vitro and in vivo. Free Radic. Biol. Med., 1994, 16, 29–33.
[21] Liochev, S. I., Fridovich, I. The Haber–Weiss cycle—70 years later: An alternative view. Redox Rep., 2002, 7, 55–57.
[22] De Grey, A. D. N. J. HO2?: The forgotten radical. DNA Cell Biol., 2002, 21, 251–257.
[23] Aikens, J.,Dix, T. A. Perhydroxyl radical (HOO?) Initiated lipid-peroxidation—The role of fatty-acid hydroperoxides. J. Biol. Chem., 1991,266, 15091–15098.
[24] Borges, F., Fernandes, E., et al. Progress towards the discovery of xanthine oxidase inhibitors. Curr. Med. Chem., 2002, 9, 195–217.
[25] Vorbach, C., Harrison, R., Capecchi, et al. Xanthine oxidoreductase is central to the evolution and function of the innate immune system. Trends Immunol., 2003,24, 512–517.
[26] Valko, M., Izakovic, M., et al. Role of oxygen radicals in DNA damage and cancer incidence. Mol. Cell. Biochem., 2004,266, 37–56.
[27] Ghafourifar, P., Cadenas, E. Mitochondrial nitric oxide synthase. Trends Pharmacol. Sci., 2005, 26, 190–195.
[28] Bergendi, L., Benes, L., Durackova, et al. Chemistry, physiology and pathology of free radicals. Life Sci., 1999, 65, 1865–1874.
[29] Koshland, D. E. The molecule of the year. Science, 1992,258, 1861.
[30] Chiueh, C. C. Neuroprotective properties of nitric oxide. Ann. N.Y. Acad. Sci., 1999, 890, 301–311.
[31] Klatt, P., Lamas, et al. Regulation of protein function by Sglutathiolation in response to oxidative and nitrosative stress. Eur. J. Biochem., 2000,267, 4928–4944.
[32] Ridnour, L. A., Thomas, D. D., et al. The chemistry of nitrosative stress induced by nitric oxide and reactive nitrogen oxide species. Putting perspective on stressful biological situations. Biol. Chem., 2004,385, 1–10.
[33] Carr, A.,McCall, et al.Oxidation of LDL by myeloperoxidase and reactive nitrogen species-reaction pathways and antioxidant protection. Arterioscl. Thromb. Vasc. Biol., 2000,20, 1716–1723.
[34] Valko, M., Rhodes, et al. Free radicals, metals and antioxidants in oxidative stress-induced cancer. Chem. Biol. Interact., 2006,160, 1–40.
[35] Halliwell, B., Gutteridge, et al. Free radicals in biology and medicine (3rd ed.). 1999 OxfordUniversity Press.
[36] Siems, W. G., Grune, et al. 4-Hydroxynonenal formation during ischemia and reperfusion of rat small-intestine. Life Sci., 1995, 57, 785–789.
[37] Stadtman, E. R. Role of oxidant species in aging. Curr. Med. Chem., 2004, 11, 1105–1112.
[38]“antioxidant”. Webster’s Third New International Dictionary, Unabridged; Merriam-Webster: 2002.
[39] Halliwell, B. How to characterize a biological antioxidant. Free Radical Res. Commun. 1990, 9, 1-32.
[40] Cadenas, E. Basic mechanisms of antioxidant activity. Biofactors, 1997, 6, 391–397.
[41] Masella, R., Di Benedetto, et al. Novel mechanisms of natural antioxidant compounds inbiological systems: Involvement of glutathione and glutathionerelated enzymes. J. Nutr. Biochem., 2005, 16, 577–586.
[42] Shen, D., Dalton, T. P., et al.Glutathione redox state regulates mitochondrial reactive oxygen production. J. Biol. Chem., 2005, 280, 25305–25312.
[43] Nogueira, C. W., Zeni, et al. Organoselenium and organotellurium compounds: Toxicology and pharmacology. Chem. Rev., 2004, 104, 6255–6285.
[44]Agamey, A., Lowe, G. M., et al. Carotenoid radical chemistry and antioxidant/pro-oxidant properties. Arch. Biochem. Biophys., 2004, 430, 37–48.
[45]Kojo, S. Vitamin C: Basic metabolism and its function as an index of oxidative stress. Curr. Med. Chem., 2004,11, 1041–1064.
[46] Landis, G. N.,Tower, J. Superoxide dismutase evolution and life span regulation. Mech. Ageing Dev., 2005,126, 365–379.
[47] Miller, E. R., Pastor-Barriuso, et al. Meta-analysis: High-dosage Vitamin E supplementation may increase all-cause mortality. Ann. Intern. Med., 2005,142, 37–46.
[48] Schrauzer, G. N. Interactive effects of selenium and chromium on mammary tumor development and growth in MMTV-infected female mice and their relevance to human cancer. Biol. Trace Element Res., 2006,109, 281–292.
[49] Sharoni, Y., Danilenko, et al. Carotenoids and transcription. Arch. Biochem. Biophys., 2004 430, 89–96.
[50] Smith, A. R., Shenvi, et al. Lipoic acid as a potential therapy for chronic diseases associated with oxidative stress. Curr. Med. Chem., 2004,11, 1135–1146.
[51] Lucarini, M.; Pedrielli, et al. Bond dissociation energies of the N-H bond and rate constants for the reaction with alkyl, alkoxyl, and peroxyl radicals of phenothiazines and related compounds. J. Am. Chem. Soc. 1999, 121, 11546-11553.
[52] Wright, J. S.,Johnson, E. R.; et al. Predicting the activity of phenolic antioxidants: theoretical method, analysis of substituent effects, and application to major families of antioxidants. J. Am. Chem. Soc. 2001, 123, 1173-1183.
[53]Quick, K. L., Hardt, et al. Rapid microplate assay for superoxide scavenging efficiency. J. Neurosci. Methods 2000, 97, 138-144.
[54]Yamashita, N., Murata, M., Inoue, S.,et al. R-Tocopherol induces oxidative damage to DNA in the presence of copper(II) ions. Chem. Res. Toxicol. 1998, 11, 855-862.
[55] Ewing, J. F.; Janero, D. R. Microplate superoxide dismutase assay employing nonenzymatic superoxide generator. Anal. Biochem. 1995, 232, 243-248.
[56] Cotton, F. A.; Wilkinson, G.; Murillo, C. A.; et al. AdVances in Inorganic Chemistry, 6th ed.; Wiley: New York, 1999; 451 .
[57] Zhao, H.; Kalivendi, S.; Zhang, H.; et al. Superoxide reacts with hydroethidine but forms a fluorescent product that is distinctly different from ethidium: potential implications in intracellular fluorescence detection of superoxide. Free Radical Biol. Med. 2003, 34, 1359-1368.
[58] Martinez-Tome, M.; Garcia-Carmona, F.; Murcia, M. A. Comparison of the antioxidants and pro-oxidants activities of broccoli amino acids with those of common food additives. J. Sci. Food Agric. 2001, 81, 1019-1026.
[59] Zhu, B. Z.; Kitrosky, N.; Chevion, M. Evidence for production of hydroxyl radicals by pentachlorophenol metabolites and hydrogen peroxide: A metal-independent organic Fenton reaction. Biochem. Biophys. Res. Commun. 2000, 270 (3), 942-946.
[60] Halliwell, B. Antioxidant characterization, methodology and mechanism. Biochem. Pharmacol. 1995, 49, 1341.
[61] Ou, B.; Hampsch-Woodill, M.; Flanagan, J.; et al. Novel fluorometric assay for hydroxyl radical prevention capacity using fluorescein as the probe. J. Agric. Food Chem. 2002, 50, 2772-2777.
[62] Sies, H.; Stahl, W. Carotenoids and UV protection. Photochem. Photobiol. Sci. 2004, 3 (8), 749-752.
[63] Zigman, S. Lens UVA photobiology. J. Ocul. Pharmocol. Ther. 2000, 16 (2), 161-165.
[64] Rozanowska, M.; Wessels, J.; Boulton, M.; et al. Blue light-induced singlet oxygen generation by retinal lipofuscin in non-polar media. Free Radical Biol. Med. 1998, 24, 1107-1112.
[65] Ebermann, R.; Alth, G.; Kreitner, M.; et al. Natural products derived from plants as potential drugs for the photodynamic destruction of tumor cells. J. Photochem. Photobiol. B 1996, 36, 95-97.
[66] Tarr, M.; Velenzeno, D. P. Singlet oxygen: the relevance of extracellular production mechanisms to oxidative stress in ViVo. Photochem. Photobiol. Sci. 2003, 2, 355-361.
[67] Martinez, G. R.; Ravanat, J. L.; Medeiros, M. H. G.; et al. Synthesis of a naphthalene endoperoxide as a source of O-18-labeled singlet oxygen for mechanistic studies. J. Am. Chem. Soc. 2000, 122, 10212-10213.
[68] Busby, R. H. M.; Hamblett, C. G. I.; Gorman, A. A. Quenching of singlet oxygen by Trolox C, ascorbate, and amino acids effects of pH and temperature. J. Phys. Chem. A 1999, 103, 7454-7459.
[69] Wilkinson, F.; Helman, W. P.; Ross, A. B. Rate constants for the decay and reactions of the lowest electronically excited singlet state of molecular oxygen in solution. An expanded and revised compilation. J. Phys. Chem. Ref. Data 1995, 24, 663-1021.
[70] Fu, Y. L.; Krasnovsky, A. A.; Foote, C. S. Quenching of singlet oxygen and sensitized delayed phthalocyanine fluorescence. J. Phys. Chem. A 1997, 101, 2552-2554.
[71] Moncada, S.; Higgs, E. A. Molecular mechanisms and therapeutic strategies related to NO. FASEB J. 1995, 9, 1319.
[72] Pryor, W. A.; Squadrito, G. L. The chemistry of peroxynitrite: a product from the reaction of NO and O2 . Am. J. Physiol. 1995, 268, L699.
[73] Squadrito, G. L.; Pryor, W. A. Mapping the reaction of peroxynitrite with CO2: energetics, reactive species, and biological implications. Chem. Res. Toxicol. 2002, 15, 885-895.
[74] Pannala, A.; Razaq, R.; Halliwell, B.; et al. Inhibition of peroxynitrite dependent tyrosine nitration by hydroxycinnamates: Nitration or electron donation? Free Radical Biol. Med. 1998, 24, 594-606.
[75] Kooy, N. W. R.; J. A.; Ischiropoulos, H.; et al. Peroxynitrite-mediated oxidation of dihydrorhodamine 123. Free Radical Biol. Med. 1994, 20, 149-156.
[76] Paquay, J. B. G.; Haenen, G. R. M. M.; Stender, G.; et al. Protection against nitric oxide toxicity by tea. J. Agric. Food Chem. 2000, 48, 5768-5772.
[77] Harman, D., Aging-A theory based on free-radical and radiation-chemistry. J. Gerontol., 1956. 11, 298-300.
[78] Valko, M., et al., Free radicals and antioxidants in normal physiological functions and human disease. Intern. J. Biochem. Cell Biol., 2007,39, 44-84.
[79] Halliwell, B., Free radicals, antioxidants and human disease : curiosity, cause, or consequence ? Lancet, 1994, 344: 721-724.
[80] Evans, M.D. and M.S. Cooke, Factors contributing to the outcome of oxidative damage to nucleic acids. BioEssays, 2004,26(5): 533-542.
[81] Valko, M., H. Morris, et al. Metals, toxicity and oxidative stress. Curr. Med. Chem., 2005. 12,1161-1208.
[82] Aust, A.E. and J.F. Eveleigh, Mechanisms of DNA Oxidation. Proc. Soc. Exp. Biol. Med., 1999. 222,246-252.
[83] Fojta, M., et al., Electrode potential-controlled DNA damage in the presence of copper ions and their complexes. Bioelectrochem., 2002. 55, 25-27.
[84] Palecek, E., et al., Electrochemical biosensors for DNA hybridization and DNA damage. Biosens. Bioelectron., 1998. 13,621-628.
[85] Labuda, J., et al., Detection of antioxidative activity of plant extracts at the DNA-modified screen-printed electrode. Sensors, 2002. 2(1), 1-10.
[86] White, B., et al., Oscillating Formation of 8-Oxoguanine during DNA Oxidation. J. Am. Chem. Soc., 2003, 125,6604-6605.
[87] Fojta, M., T. Kubicarova, and E. Palecek, Electrode potential-modulated cleavage of surface-confined DNA by hydroxyl radicals detected by an electrochemical biosensor. Biosens. Bioelectron., 2000. 15, 107-115.
[88] Cadenas, E., Basic mechanisms of antioxidant activity. Biofactors, 1997. 6,391-397.
[89] McCord, J.M. and I. Fridovich, Superoxide dismutase an enzymic function for erythrocuprein Hemocuprein. J. Biol. Chem., 1969. 244,6049-6055.
[90] Chance, B., H. Sies, and A. Boveris, Hydroperoxide metabolism in mammalian organs. Physiol. Rev., 1979. 59,527-605.
[91] Maiorino, M., et al., Phospholipid hydroperoxide glutathione peroxidase is the 18 kDa selenoprotein expressed in human tumor cell lines. J. Biol. Chem., 1991. 266,7728-7732.
[92] Huang, D., B. Ou, et al. The Chemistry behind Antioxidant Capacity Assays. J. Agric. Food Chem., 2005. 53,1841-1856.
[93] Antolovich, M., et al., Methods for testing antioxidant activity. Analyst, 2002, 127,183-198.
[94] Wayner, D.D.M., et al., Quantitative measurement of the total, per oxyl radical-trapping antioxidant capability of human blood plasma by controlled peroxidation. FEBS Lett., 1985,187,33-37.
[95] Cao, G.H., H.M. et al. Oxygen-radical absorbency capacity assay for antioxidants. Free Radical Biol.Med., 1993, 14,303-311.
[96] Miller, N.J., et al., A Novel method for measuring antioxidant capacity and its application to monitoring antioxidant status in premature neonates. Clin. Sci., 1993, 84, 407-412.
[97] Benzie, I.F.F. and J.J. Strain, The ferric reducing ability of plasma as a measure of antioxidant power the FRAP assay,. Anal. Biochem., 1996, 239:70-76.
[98] Blois, M.S., Antioxidant determinations by the use of a stable free radical. Nature, 1958, 181: 1199-1200.
[99] Korotkova, E.I., Y.A. Karbainov, et al. Investigation of antioxidant and catalytic properties of some biologically active substances by voltammetry. Anal. Bioanal. Chem., 2003, 375: 465-468.
[100] Bukova, M., et al., Detection of damage to DNA and antioxidative activity of yeast polysaccharides at the DNA-modified screen-printed electrode. Talanta, 2002, 56: 939-947.
[101] Liu, J., et al., Antioxidant Sensors Based on DNA-Modified Electrodes. Anal. Chem., 2005, 77(23): 7687-7694.
[102] Liu, J., et al., Generation of OH radicals at palladium oxide nanoparticle modified electrodes, and scavenging by fluorescent probes and antioxidants. J. Electroanal. Chem., 2008,619-620: 131-136.
[103] Campanella, L., et al., Determination of antioxidant properties of aromatic herbs,olives and fresh fruit using an enzymatic sensor. . Anal. Bioanal. Chem., 2003, 375: 1011-1016.
[104] Campanella, L., E. Martini, and M. Tomassetti, Antioxidant capacity of the algae using a biosensor method. Talanta, 2005,66: 902-911.
[105] Campanella, L., A. Bonanni, and M. Tomassetti, Determination of the antioxidant capacity of samples of different types of tea, or of beverages based on tea or other herbal products, using a superoxide dismutase biosensor. J. Pharm. Biomed. Anal. , 2003, 32: 725-736.
[106] Campanella, L., et al., Biosensors for determination of total and natural antioxidant capacity of red and white wines: comparison with other spectrophotometric and fluorimetric methods. Biosens. Bioelectron., 2004, 19: 641-651.
[107] Campanella, L.,et al., Biosensors for determination of total antioxidant capacity ofphytotherapeutic integrators: comparison with other spectrophotometric, fluorimetric and voltammetric methods. J. Pharm. Biomed. Anal. , 2004, 35: 303-320
[108] Campanella, L., et al., Comparison of fluorimetric, voltammetric and biosensor methods for the determination of total antioxidant capacity of drug products containing acetylsalicylic acid., in J. Pharm. Biomed. Anal. 2004, 91-99.
[109] Campanella, L., et al., New biosensor for superoxide radical used to evidence molecules of biomedical and pharmaceutical interest having radical scavenging properties. J. Pharm. Biomed. Anal. , 2000, 23: 69-76.
[110] Korotkova, E.I., Y.A. Karbainov, and A.V. Shevchuk, Study of antioxidant properties by voltammetry. J. Electroanal. Chem., 2002,518: 56-60.
[111] Avramchik, O.A., et al., Antioxidant and electrochemical properties of calcium and lithium ascorbates. J. Pharm. Biomed. Anal., 2005,37: 1149-1154.
[112] Bashkatova, N.V., et al., Electrochemical, quantum-chemical and antioxidant properties of antipyrine and its derivatives. J. Pharm. Biomed. Anal., 2005, 37: 1143-1147.
[113] Korotkova, E.I., et al., Study of antioxidant properties of a water-soluble Vitamin E derivative-tocopherol monoglucoside (TMG) by differential pulse voltammetry. Talanta, 2004,63: 729-734.
[114] Kong, Y.-T., et al., Peroxidase-Based Amperometric Sensor for the Determination of Total Phenols Using Two-Stage Peroxidase Reactions. . Am. J. Enol. Vitic., 2001,52: 381-385.
[115] Prieto-Simon, B., et al., Electrochemical biosensors as a tool for antioxidant capacity assessment. Sens. Actuators, B, 2008, 129: 459-466.
[116] Fojta, M., et al., A supercoiled DNA-modified mercury electrode-based biosensor for the detection of DNA strand cleaving agents. Talanta, 1998,46: 155-161.
[117] Fojta, M. and E. Palecek, Supercoiled DNA-modified mercury electrode: A highly sensitive tool for the detection of DNA damage. Anal. Chim. Acta, 1997,342: 1-12.
[118] Palecek, E. and M. Fojta, Detecting DNA hybridization and damage. Anal. Chem., 2001, 73: 74A-83A.
[119] Fojta, M., L. Havran, and E. Palecek, Chronopotentiometric detection of DNA strand breaks with mercury electrodes modified with supercoiled DNA. Electroanalysis, 1997,9: 1033-1034.
[120] Mugweru, A. and J. Rusling, Studies of DNA Damage Inhibition by Dietary Antioxidants Using Metallopolyion/DNA Sensors. Electroanalysis, 2006,18: 327-332.
[121] Liu, J., et al., Anal. Chem., 2006,78: 6879-6884.
[122] Zhou, L., et al., Toxicity Screening by Electrochemical Detection of DNA Damage by Metabolites Generated In Situ in Ultrathin DNA-Enzyme Films. J. Am. Chem. Soc., 2003, 125(5): 1431-1436.
[123] Thorp, H.H., Cutting out the middleman: DNA biosensors based on electrochemical oxidation. Trends Biotechnol., 1998, 16(3): 117-121.
[124] Wang, B. and J.F. Rusling, Voltammetric Sensor for Chemical Toxicity Using[Ru(bpy)2poly(4-vinylpyridine)10Cl)]+ as Catalyst in Ultrathin Films. DNA Damage from Methylating Agents and an Enzyme-Generated Epoxide. Anal. Chem., 2003, 75(16): 4229-4235.
[125] Labuda, J., Anal. Bioanal. Chem. , 2009, 394: 855-861.
[126] Huang, M., et al., Alternate Assemblies of Platinum Nanoparticles and Metalloporphyrins as Tunable Electrocatalysts for Dioxygen Reduction. Langmuir, 2005, 21:323-329.
[127] Wang, B., et al., Sol?Gel Thin-Film Immobilized Soybean Peroxidase Biosensor for the Amperometric Determination of Hydrogen Peroxide in Acid Medium. Anal. Chem. , 1999, 71: 1935-1939.
[128] Zhang, G. and P.K. Dasgupta, Hematin as a peroxidase substitute in hydrogen peroxide determinations. . Anal. Chem., 1992, 64: 517-522.
[129] Zhou, H., et al., Hemoglobin-Based Hydrogen Peroxide Biosensor Tuned by the Photovoltaic Effect of Nano Titanium Dioxide. Anal. Chem. , 2005, 77: 6102-6104.
[130] Shi, C. and F.C. Anson, Inorg. Chem. , 1998,37: 1037-1043.
[131] Shen, Y., et al., Electroanalysis, 2002, 14: 1557- 1563.
[132] Shi, C. and F.C. Anson, Inorg. Chem., 1995, 34: 4554-4561.
[133]Finnen, D.C., et al., Structures and Spectroscopic Characteristics of Iron(II1) Diethylenetriaminepentaacetic Acid Complexes. A Non-Heme Iron(III) Complex with Relevance to the Iron Environment in Lipoxy genases. . Inorg. Chem., 1991,30: 3960-3964.
[134] Nazeeruddin, M. K., etal., Conversion of Light to Electricity by cis-XzBis( 2,2’-bipyridyl-4,4’-dicarboxylate)ruthenium( 11) Charge-Transfer Sensitizers (X = C1-, Br-, I-, CN-, and SCN-) on Nanocrystalline Ti02 Electrodes. J. Am. Chem. Soc., 1993, 115: 6382-6390.
[135] Meier, K.-R. and M. Gratzel, Redox targeting of oligonucleotides anchored to nanocrystalline TiO2 films for DNA detection. ChemPhysChem, 2002,3:371-374.
[136] Shinohara, H., et al., Bioelectrochem. Bioenerg. , 1991,26: 307-320.
[137] Topoglidis, E., et al., Protein Adsorption on Nanocrystalline TiO2 Films: An Immobilization Strategy for Bioanalytical Devices. Anal. Chem., 1998,70(23): 5111-5113.
[138] Topoglidis, E., et al., Protein adsorption on nanoporous: a novel approach TiO2 to studying photoinduced protein/electrode transfer reactions. Faraday Discuss., 2000, 116: 35-46.
[139] Rajh, T., et al., Surface Restructuring of Nanoparticles: An Efficient Route for Ligand-Metal Oxide Crosstalk. J. Phys. Chem. B 2002, 106: 10543-10552.
[140] Moser, J., et al., Surface Complexation of Colloidal Semiconductors Strongly Enhances Interfacial Electron-Transfer Rates. Langmuir, 1991, 7: 3012-3018.
[141] Ishibashi, K., et al., Detection of active oxidative species in TiO2 photocatalysis using the fluorescence technique. Electrochem. Commun., 2000, 2: 207-210.
[142] Ishibashi, K., et al., Quantum yields of active oxidative species formed on TiO2 photocatalyst. J. Photochem. Photobiol., A, 2000, 134: 139-142.
[143] Shen, Y., M. Trauble, and G. Wittstock, Detection of Hydrogen Peroxide Produced duringElectrochemical Oxygen Reduction Using Scanning Electrochemical Microscopy. Anal. Chem., 2008, 80: 750-759.
[144] Balbuena, P.B., et al., Adsorption and Dissociation of H2O2 on Pt and Pt-Alloy Clusters and Surfaces. J. Phys. Chem. B, 2006, 110: 17452-17459.
[145] Heyrovsky, M. and S. Vavricka, Heterogeneous electron transfer to molecular oxygen in aqueous solutions. J. Electroanal. Chem., 1992. 332: 309-313.
[146] Popovi?, T., et al., Synthesis and etructure of dehydro-4-iminoallantoin and its covealent adducts. Tetrahedron, 1991, 47: 317-322.
[147] Skinner, W.A. and P. Alaupovic, Oxidation Products of Vitamin E and Its Model, 6-Hydroxy-2,2,5,7,8-pentamethylchroman. V. Studies of the Products of Alkaline Ferricyanide Oxidation. J. Org. Chem. , 1963, 28: 2854-2858.
[148] Nanni, E.J., M.D. Stallings Jr., and D.T. Sawyer, Does Superoxide Ion Oxidize Catechol, a-Tocopherol, and Ascorbic Acid by Direct Electron Transfer? J. Am. Chem. Soc. , 1980, 102: 4481-4485.
[149] Thomas, M.J. and B.H.J. Bielskit, Oxidation and Reaction of Trolox c, a Tocopherol Analogue, in Aqueous Solution. A Pulse-Radiolysis Study. J. Am. Chem. Soc. , 1989, 111: 3315-3319.
[150] Priyadarsini, K.I., S. Kapoor, and D.B. Naik, One- and Two-Electron Oxidation Reactions of Trolox by Peroxynitrite. Chem. Res. Toxicol. , 2001,14: 567-571.
[151] Santos, C.X.C., E.I. Anjos, and O. Augusto, Uric Acid Oxidation by Peroxynitrite: Multiple Reactions, Free Radical Formation, and Amplification of Lipid Oxidation. Arch. Biochem. Biophy., 1999,372: 285-294.
[152] Ozgen, M., et al., Modified 2,2-Azino-bis-3-ethylbenzothiazoline-6-sulfonic Acid (ABTS) Method to Measure Antioxidant Capacity of Selected Small Fruits and Comparison to Ferric Reducing Antioxidant Power (FRAP) and 2,2‘-Diphenyl-1-picrylhydrazyl (DPPH) Methods. J. Agric. Food Chem., 2006,54: 1151-1157.
[153] K.-H. Yoo, D. H. Ha, J.-O Lee, et al. Choi, Electrical Conduction through Poly(dA)-Poly(dT) and Poly(dG)-Poly(dC) DNA Molecules. Phys. Rev. Lett. 2001, 87: 198102 (1-4).
[154] S. Delaney, J. K. Barton, Long-Range DNA Charge Transport, J. Org. Chem. 2003, 68, 6475-6483
[155] S. O. Kelley, J. K. Barton, Electrochemistry of Methylene Blue Bound to a DNA-Modified Electrode. Bioconjugate Chem. 1997, 8, 31-37.
[156] E. M. Boon, N. M. Jackson, M. D. Wightman, et al. Intercalative Stacking: A Critical Feature of DNA Charge-Transport Electrochemistry. J. Phys. Chem. B 2003, 107, 11805-11812.
[157] E. M. Boon, J.K. Barton, DNA Electrochemistry as a Probe of Base Pair Stacking in A-, B-,and Z-Form DNA. Bioconjugate Chem. 2003, 14, 1140-1147.
[158] A. K. Boal, J. K. Barton.Electrochemical Detection of Lesions in DNA. Bioconjugate Chem. 2005, 16, 312-321.
[159] S. O. Kelley, E. M. Boon, J. K. Barton, et al.Single-base mismatch detection based on charge transduction through DNA, Nucleic Acids Research, 1999, 27: 4830-4837.
[160] H.-W. Fink, C. Schonenberger. Electrical Conduction Through DNA Molecules. Nature 1999, 398:407-410.
[161] D. Porath, A. Bezryadin, S. de Vries, et al. Direct Measurement of Electrical Transport through DNA Molecules. Nature 2000, 403:635-638.
[162] E. L. S. Wong, J. Justin Gooding. The Electrochemical Monitoring of the Perturbation of Charge Transfer through DNA by Cisplatin. J. Am. Chem. Soc. 2007, 129: 8950-8951.
[163] Derfus, A. M., Chan, W. C. W., et al. Probing the cytotoxicity of semiconductor quantum dots. Nano Lett. 2004,4:11–18.
[164] P.R. Leroueil,S?. Hong,A. Mecke, ?et al. Holl.Nanoparticle Interaction with Biological Membranes. Acc. Chem. Res. 2007, 40, 335–342.
[165] Y. Jin, S. Kannan, M. Wu, et al. Toxicity of Luminescent Silica Nanoparticles to Living Cells. Anal. Chem., 2007, 79: 9150 -9159.
[166] J. A. Ryan, K. W. Overton, M. E. Speight, et al.Cellular Uptake of Gold Nanoparticles Passivated with BSA-SV40 Large T Antigen Conjugates. Nano Lett. 2006, 6: 1121-1125.
[167] A. Magrez, S. Kasas, V. Salicio, et al.Cellular Toxicity of Carbon-Based Nanomaterials. Langmuir, 2007, 23: 12783 -12787.
[168] N. Ma, J. Yang, K. M. Stewart, et al. DNA-Passivated CdS Nanocrystals: Luminescence, Bioimaging, and Toxicity Profiles. Nano Lett., 2007, 7: 3592 -3597.
[169] DNA Damage Induced by Multiwalled Carbon Nanotubes in Mouse Embryonic Stem Cells. L. Zhu, D. W. Chang, L. Dai, Y. Hong.
[170] Shik Chi Tsang, Chih Hao Yu,Xin Gao, Silica-Encapsulated Nanomagnetic Particle as a New Recoverable Biocatalyst Carrier ; J. Phys. Chem. B 2006, 110, 16914-16922.
[171] Elicia L. S. Wong and J. Justin Gooding;The Electrochemical Monitoring of the Perturbation of Charge Transfer through DNA by Cisplatin; J. AM. CHEM. SOC. 2007, 129, 8950-8951.
[172] Wong, E. L. S.; Gooding, J. J. Anal. Chem. 2006, 78, 2138.
[173] T. Rajh, L. X. Chen, K. Lukas, et al. Tiede;Surface Restructuring of Nanoparticles: An Efficient Route for Ligand-Metal Oxide Crosstalk; J. Phys. Chem. B 2002, 106, 10543-10552.
[174] Zeni, G. and R.C. Larock, Synthesis of heterocycles via palladium-catalyzed oxidation addition. Chem, Rev., 2006, 106: 4644-4680.
[175] Jifeng Liu, Christophe Roussel,Gre? goire Lagger, et al. Antioxidant Sensors Based on DNA-Modified Electrodes; Anal. Chem. 2005, 77, 7687-7694.
[176] Jeff Gore, Zev Bryant, Marcelo No¨llmann, et al.DNA overwinds when stretched Nature. 44217 August 2006.
[177] Bryant,Z. etal. Structural transitionsan delasticity from torque measurements on DNA. Nature 424, 2003.
[178] Smith,S.B.,Cui,Y.,Bustamante,C. Over stretching B-DNA: the elastic response of individual double-stranded and single-stranded DNA molecules. Science 271, 1996.
[179] Gore,J. Single-Molecule Studies of DNA Twist Mechanics and Gyrase Mechanochemistry. Thesis,Univ. California, Berkeley, 2005.
[180] Wang,M.D.,Yin,H.,etal.Stretching DNA with optical tweezers. Biophys.J. 72, 1335¨C-1346,1997.