摘要
在水相中制备了聚乙烯亚胺(PEI)包裹的水溶性PEI-CdZnTe量子点。研究了反应时间,酸度及不同常见金属离子对PEI-CdZnTe量子点荧光效率的影响。基于Pb~(2+)对CdZnTe量子点具有选择性荧光猝灭作用,建立了用CdZnTe量子点为探针灵敏测定痕量Pb~(2+)的新方法。研究了不同浓度Pb~(2+)对CdZnTe量子点荧光强度猝灭情况,结果表明,Pb~(2+)对CdZnTe量子点的荧光猝灭过程可以很好地用Stern-Volmer荧光猝灭方程来描述。当Pb~(2+)浓度在0.05~3.0μg·mL~(-1)范围内,CdZnTe量子点的荧光强度F_0/F与Pb~(2+)浓度之间具有较好的线性关系,线性相关系数为0.998 8,检测限为0.01μg·mL~(-1)。该量子点荧光分析方法简便快速、灵敏度高、选择性好,能够应用于实际水样中Pb~(2+)的分析与测定。
Water-soluble CdZnTe quantum dots(QDs)were firstly synthesized by using 3-mercaptopropionic acid(MPA)as modifier in aqueous phase.Then,CdZnTe quantum dots were capped with polyethyleneimine(PEI)with electrostatic interaction and condensation reaction between carboxyl group on the surface of QDs and amino group of PEI,and several metal ions were tested to check if they affect the fluorescence properties of CdZnTe QDs in the paper.A novel method to detect trace Pb~(2+) has been developed based on the selective fluorescence quenching Pb~(2+) to PEI-CdZnTe QDs.Fluorescence quenching effect of PEICdZnTe QDs had been studied by increasing the Pb~(2+) concentration.The study results show that fluorescence quenching process of Pb~(2+) can be described well by Stern-Volmer fluorescence quenching equation.There is a good linear relationship between the fluorescence intensity F_0/F and the concentration of Pb~(2+) when the concentration of Pb~(2+) is in the ranges of 0.05~3.0μg·mL~(-1).The linear correlation coefficient and the detection limits are 0.998 8and 0.01μg·mL~(-1),respectively.The proposed fluorescence method of detection is simple,rapid and sensitive,which has been successfully applied to the detection of Pb~(2+) in tap water.
引文
[1]CAO Yi-sheng(曹异生).China Metal Bulletin(中国金属通报).2008,43:34.
[2]CHEN Tian-jin,WEI Yi-min,PAN Jia-rong(陈天金,魏益民,潘家荣).Food and Nutrition in China(中国食物与营养),2007,2:15.
[3]LIU Lan(刘岚).Occupation and Health(职业与健康),2005,21(5):665.
[4]Cigdem E,Senkal F B,Yaman M.Food Chemistry,2013,137:55.
[5]Ghazale D T,Farzaneh S.Talanta,2013,115:744.
[6]Erkan Y,Mustafa S.Talanta,2013,116:882.
[7]Teslima D,Serife S,Ahmet U,et al.Food Chemistry,2015,174:591.
[8]SUN Bo-si,REN Ting,ZHAO Li-jiao,et al(孙博思,任婷,赵丽娇,等).Spectroscopy and Spectral Analysis(光谱学与光谱分析),2015,32(10):2847.
[9]Naditnan P,Poomrat R,Ratthapol R,et al.Sensor and Actuators B:Chemical,2015,207:526.
[10]PAN Tao,ZHANG Xia,FU Chang-e,et al(潘涛,张霞,符嫦娥,等).Chinese Journal of Analytical Chemsitry(分析化学),2014,42(10):1501.
[11]Li Z,Yu L B,Liu Y B,et al.Electrochimica Acta,2015,153:200.
[12]Weng C I,Chang H T,Lin C H,et al.Biosensors and Bioelectronics,2015,64:182.
[13]Cheng J W,Li D M,Cheng T,et al.Journal of Alloys and Compounds,2014,589:539.
[14]WANG Guang-li,DONG Yu-ming,XU Jing-juan,et al(王光丽,董玉明,徐静娟,等).Scientia Sinica Chimica(中国科学:化学),2010,40(8):1114.
[15]Zhang J,Zhao S Q,Zhang K,et al.Chemosphere,2014,95:105.
[16]Dong B H,Cao L X,Su G,et al.Journal of Colloid and Interface Science,2009,339:78.
[17]Yang M,Han A J,Duan J L,et al.Journal of Hazardous Materials,2012,237-238:63.
[18]CHEN Yan-qing,LONG Guan-hong(陈燕清,龙冠虹).Journal of Nanchang University:Natural Science(南昌大学学报:理科版),2014,38(6):569.