jf8b07201_si_001.pdf (464 kB)
Download fileFabricating an Acetylcholinesterase Modulated UCNPs-Cu2+ Fluorescence Biosensor for Ultrasensitive Detection of Organophosphorus Pesticides-Diazinon in Food
journal contribution
posted on 2019-03-19, 00:00 authored by Pingyue Wang, Huanhuan Li, Md Mehedi Hassan, Zhiming Guo, Zheng-Zhu Zhang, Quansheng ChenIn
this study, a highly sensitive upconversion fluorescence (FL)
biosensor was developed for the detection of organophosphorus pesticides
(OPs) based on an acetylcholinesterase (AChE) modulated FL “off–on–off”
strategy. The luminescence of synthesized UCNPs could be quenched
strongly by Cu2+ due to an energy transfer effect. Upon
addition of AChE and acetylthiocholine (ATCh), the enzymatic
hydrolysate (thiocholine) could seize Cu2+ from UCNPs-Cu2+ mixture, resulting in the quenched FL triggered on. OPs
could irreversibly impede the activity of AChE, which caused the formation
of thiocholine to decrease, thus, reduced the recovery of FL. Under
the optimum conditions, a linear detection range from 0.1 to 50 ng/mL
was achieved for the representative OPs (diazinon) with LOD of 0.05
ng/mL. Furthermore, the ability of the biosensor to detect OPs was
also confirmed in adulterated environmental and agricultural samples.
In validation analysis, the proposed sensor showed satisfactory results
(p > 0.05) with GC–MS.