Electrochemical biosensing of carbaryl based on acetylcholinesterase immobilized onto electrochemically inducing porous graphene oxide network

This work describes a sensitive electrochemical biosensor for detection of carbamate pesticides based on immobilization of acetylcholinesterase (AChE) on the electrochemically inducing porous graphene oxide network (e-pGON) which is prepared by scanning the GO modified electrode using successive cyclic voltammetry method. The e-pGON effectively promotes the electron transfer rate and facilitates the access of substrates to the active centers. The as-prepared biosensor shows high affinity to acetylthiocholine (ATCl) with a Michaelis-Menten constant value of 0.45 mmol L-1. Under optimum conditions, the inhibition of carbaryl is proportional to its concentration ranging from 0.3 to 6.1 ng/mL. The detection limit is 0.15 ng/mL. The developed biosensor exhibits good performance such as reproducibility and stability, thus providing a promising tool for the analysis of enzyme inhibitors. (C) 2016 Elsevier B.V. All rights reserved.