A “signal-on’’ aptasensor for simultaneous detection of chloramphenicol and polychlorinated biphenyls using multi-metal ions encoded nanospherical brushes as tracers

摘要: Abstract A “signal-on’’ aptasensor was developed for simultaneous detection of chloramphenicols (CAP) and polychlorinated biphenyl-72 (PCB72) with a novel multi-metal ions encoded nanospherical brushes as nanotracers. To construct the assay, respective aptamer CAP PCB72 labeled magnetic gold nanoparticles capture probes (aptamer-MGPs), their complementary single strand DNA (s-DNA) metal (Cd 2+ Pb ) on branched polyethylene imine tracers (s-DNA-MSPEIs), were simultaneously synthesized. After that, probe connected through hybridization reaction between s-DNA aptamers. In presence PCB72, analytes could react aptamers release into supernatant after separation. The released be detected square wave voltammetry (SWV) without acid dissolution, which can switch signals biosensor to “on’’ state. Under optimal conditions, assay detect low 0.3 pg mL −1 dynamitic range from 0.001 100 ng mL exhibited excellent selectivity. More importantly, strategy extended easily other targets changing corresponding tracers, provides promising facile approach in multiplex ultra-trace level pollutants food safety more complex separation washing steps.