کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1175054 | 1491335 | 2016 | 11 صفحه PDF | دانلود رایگان |
Here, a highly sensitive electrochemical aptasensor based on a novel signal amplification strategy for the determination of bisphenol A (BPA) was developed. Construction of the aptasensor began with the deposition of highly dispersed platinum nanoparticles (PtNPs)/acid-oxidized carbon nanotubes (CNTs–COOH) functionalized with polyethyleneimine (PEI) at the surface of glassy carbon (PtNPs/PEI/CNTs–COOH/GC) electrode. After immobilizing the amine-capped capture probe (ssDNA1) through the covalent amide bonds formed by the carboxyl groups on the nanotubes and the amino groups on the oligonucleotides, we employed a designed complementary BPA–aptamer (ssDNA2) as a detection probe to hybridize with the ssDNA1. By adding BPA as a target, the aptamer specifically bound to BPA and its end folded into a BPA-binding junction. Because of steric/conformational restrictions caused by aptamer–BPA complex formation at the surface of modified electrode, the interfacial electron transfer of [Fe(CN)6]3−/4− as a probe was blocked. Sensitive quantitative detection of BPA was carried out by monitoring the decrease of differential pulse voltammetric responses of [Fe(CN)6]3−/4− peak current with increasing BPA concentrations. The newly developed aptasensor embraced a number of attractive features such as ease of fabrication, low detection limit, excellent selectivity, good stability and a wide linear range with respect to BPA.
Journal: Analytical Biochemistry - Volume 512, 1 November 2016, Pages 47–57