摘要
This work reports a sensitive amperometric biosensor for organophosphate pesticides （OPs） fabricated through modifying glassy carbon electrode with acetylcholinesterase （ACHE） immobilized on graphene/polyaniline （G/PANI） composite film. The obtained G/PANI composite films show large specific area, high conductivity, good biocompatibility, and fast redox properties and have perfect layered and encapsulated structures. The as-prepared biosensor shows high affinity to acetylthiocholine （ATC1） with a Micbaelis-Menten constant value of 0.20 mmol/L. Furthermore, based on the inhibition of the enzymatic activity （immobilized ACHE） caused by the model compound of carbaryl （one kind of pesticides）, it is found that the inhibition activity of carbaryl is proportional to its concen- tration ranging from 38 to 194 ngomL-1. The developed biosensor shows a detection limit of 20 ngomL-1 （S/N~ 3） for OPs detection and exhibits good performance such as good reproducibility and acceptable stability, which makes it possible to provide a new and promising tool for the analysis of enzyme inhibitors.
This work reports a sensitive amperometric biosensor for organophosphate pesticides （OPs） fabricated through modifying glassy carbon electrode with acetylcholinesterase （ACHE） immobilized on graphene/polyaniline （G/PANI） composite film. The obtained G/PANI composite films show large specific area, high conductivity, good biocompatibility, and fast redox properties and have perfect layered and encapsulated structures. The as-prepared biosensor shows high affinity to acetylthiocholine （ATC1） with a Micbaelis-Menten constant value of 0.20 mmol/L. Furthermore, based on the inhibition of the enzymatic activity （immobilized ACHE） caused by the model compound of carbaryl （one kind of pesticides）, it is found that the inhibition activity of carbaryl is proportional to its concen- tration ranging from 38 to 194 ngomL-1. The developed biosensor shows a detection limit of 20 ngomL-1 （S/N~ 3） for OPs detection and exhibits good performance such as good reproducibility and acceptable stability, which makes it possible to provide a new and promising tool for the analysis of enzyme inhibitors.
基金
Acknowledgement The authors thank the National Natural Science Foundation of China （Nos. 21407100, 21574076, 61504076 and 21501113）, the Natural Science Foundation of Shanxi Province （No. 2014011016-1）, and the Program for the Top Young and Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi （No. 02035290 1014）.
