Organophosphorus pesticides detection using acetylcholinesterase biosensor based on gold nanoparticles constructed by electroless plating on vertical nitrogen-doped single-walled carbon nanotubes

摘要

An acetylcholinesterase (AChE) biosensor was constructed based on gold nanoparticles (AuNPs) using electroless plating on vertical nitrogen-doped single-walled carbon nanotubes (VNSWCNTs) for detecting organophosphorus pesticides (OPs). AChE was immobilised on AuNPs via Au-S bonding, and VNSWCNTs were produced by spontaneous chemical adsorption of NSWCNTs on gold electrode, also via Au-S bonding. This modified electrode exhibited excellent electron transfer capacity due to the synergy between AuNPs and VNSWCNTs. The developed biosensor showed good linear relations at concentrations of 10(-5)-1ppb, and the detection limits were 3.04x10(-6)ppb for methyl parathion, 1.96x10(-6)ppb for malathion and 2.06x10(-6)ppb for chlorpyrifos, respectively. The AChE biosensor revealed satisfactory stability, excellent sensitivity and good repeatability. These results suggest that this biosensor has good application prospects and can function as a sensitive device in OPs analysis.