A new amplified impedimetric aptasensor based on the electron transfer ability of Au nanoparticles and their affinity with aptamer

摘要: Abstract Taking the advantages of excellent electron transfer ability gold nanoparticles (AuNPs) and their unique interaction with aptamer, a novel electrochemical aptasensor has been developed used to sensitively detect target model, adenosine triphosphate (ATP). Briefly, because between AuNPs nitrogen-containing bases, ATP-binding aptamer (ABA) which is immobilized on electrode can directly adsorb AuNPs. Thus, redox probe [Fe(CN) 6 ] 3 −/4 − be greatly promoted. In presence ATP, formed ABA-ATP complex poor affinity results in large electron-transfer resistance (R et ) owing negatively charged ATP phosphate backbones ABA. Here, change interfacial feature was characterized by impedance spectroscopy without any modification were employed as signal amplifiers. The demonstrated that label-free could low 0.54 nM wide linear range from 1.0 nM 100.0 μM, great promising applications sensitive assays other small molecules proteins.