Photoelectrochemical Immunosensor Array Based on Thioglycolic Acid Capped CdS Quantum Dots for Multiplexed Detection of Veterinary Drug Residues

• Published in: Chinese journal of chemistry 2012-05, Vol.30 (5), p.1168-1176
• Main Author: 肖飞 赖彦君 张苧丹 白静 鲜跃仲 金利通
• Format: Article
• Language: English
• Subjects: CdS; CdS quantum dots; Electrodes; immunosensor array; photoelectrochemical; Quantum dots; Transplants & implants; veterinary drug; 二甲基二烯丙基氯化铵; 传感器阵列; 光电化学; 免疫; 兽药残留检测; 巯基乙酸; 量子点
• ISSN: 1001-604X; 1614-7065
• DOI: 10.1002/cjoc.201100548

A photoelectrochemical immunosensor based on multi-electrode array was developed for simultaneous and sen- sitive determination of veterinary drug residues. In this system, poly（dimethyldiallylammonium chloride） （PDDA）, Au nanoparticles （Au NPs） and thioglycolic acid （TGA）-capped CdS quantum dots （QDs） were layer-by-layer as- sembled onto the home-made Au electrode array. The assembling process of the （CdS/PDDA/Au NPs/PDDA）, mul- tilayer was characterized by electrochemical impedance spectroscopy. And then the antibodies for clenbuterol （CB）, ractopamine （RAC） and chloramphenicol （CAP） were covalently immobilized onto the Au electrode array by 1-ethyl-3-（3-dimethylaminopropyl） carbodiimide （EDC） coupling reaction, respectively. The concentrations of CB, RAC and CAP were measured based on the photoelectrochemical effects of CdS QDs. Under the optimal conditions the limits of detection （LOD） for CB, RAC and CAP were 25, 50 and 2.2 pg/mL （3a）, respectively, with acceptable recovery over the range of 95.40%--105.5% in pig liver samples. All results indicate that the immunosensor array system has potential application for practical, effective and high throughput analysis of veterinary drugs residues.