کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
870182 | 909854 | 2007 | 5 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Immobilization of acetylcholinesterase on gold nanoparticles embedded in sol–gel film for amperometric detection of organophosphorous insecticide Immobilization of acetylcholinesterase on gold nanoparticles embedded in sol–gel film for amperometric detection of organophosphorous insecticide](/preview/png/870182.png)
A simple method to immobilize acetylcholinesterase (AChE) on silica sol–gel (SiSG) film assembling gold nanoparticles (AuNPs) was proposed, thus a sensitive, fast and stable amperometric sensor for quantitative determination of organophosphorous insecticide was developed. The large quantities of hydroxyl groups in the sol–gel composite provided a biocompatible microenvironment around enzyme molecule and stabilized its biological activity to a large extent. The immobilized AChE could catalyze the hydrolysis of acetylthiocholine chloride (ATCl) with a Kmapp value of 450 μM to form thiocholine, which was then oxidized to produce detectable single with a linear range of 10–1000 μM. AuNPs catalyzed the electro-oxidation of thiocholine, thus increasing detection sensitivity. Based on the inhibition of organophosphorous insecticide on the enzymatic activity of AChE, using monocrotophos as a model compound, the conditions for detection of the insecticide were optimized. The inhibition of monocrotophos was proportional to its concentration ranging from 0.001 to 1 μg/ml and 2 to 15 μg/ml, with the correlation coefficients of 0.9930 and 0.9985, respectively. The detection limit was 0.6 ng/ml at a 10% inhibition. The developed biosensor exhibited good reproducibility and acceptable stability, thus providing a new promising tool for analysis of enzyme inhibitors.
Journal: Biosensors and Bioelectronics - Volume 23, Issue 1, 30 August 2007, Pages 130–134