A dual-signaling strategy for ultrasensitive detection of bisphenol A by aptamer-based electrochemical biosensor
A facile label-free aptamer-based electrochemical biosensor has been developed for sensitive detection of bisphenol A (BPA) based on a dual-signaling amplification strategy.The aptasensor was constructed by electrodeposition of gold nanoparticles (AuNPs) onto a glassy carbon electrode (GCE),where a thiolated-modified BPA aptamer was immobilized through self-assembly and then hybridized with the biotin-modified complementary DNA probe (cDNA) to form a double-stranded DNA.Upon the highly specific interaction between the target BPA and its aptamer,cDNA was released from the electrode surface and BPA was immobilized on the sensing interface.Streptavidin-modified horseradish peroxidase-functionalized gold nanoparticle (avidin-HRP-AuNP) was chosen as the nanoprobe,due to its catalytic activity to the oxidation of hydroquinone (HQ) in the presence of H2O2.As a result,the captured amounts of avidin-HRP-AuNP decrease with the increase of the BPA concentration and produce a series of decreasing catalytic peak currents.In addition,BPA has a redox activity and could provide an additional signal transformation.By superimposing the two signal changes,BPA was detected sensitively in a linear range from 0.001 to 1 nM with a detection limit of 0.41 pM.The aptasensor exhibited good selectivity toward BPA even in the presence of the interferents at 100-fold concentrations.This method would be readily applicable for sensitive detection of other redox analytes,merely by changing the anti-BPA aptamer/cDNA pair with a correspondent anti-target molecule aptamer and cDNA.
Aptamer Complementary DNA sequences Bisphenol A Horseradish peroxidase-functionalized gold nanoparticle Dual-signaling amplification
Yujie Liu Yun Liu Baohong Liu
Department of Chemistry,State Key Lab of Molecular Engineering of Polymers and Institutes of Biomedical Sciences,Fudan University,Shanghai 200433,China
国际会议
南京
英文
265-271
2016-12-23（万方平台首次上网日期，不代表论文的发表时间）