A photoelectrochemical sensor based on an acetylcholinesterase-CdS/ZnO-modified extended-gate field-effect transistor for glyphosate detection. Issue 14 (23rd June 2021)

• Record Type: Journal Article
• Authors: Yu, Jiarui; Lin, Jingyu; Li, Jianping
• Is Part Of: Analyst. Volume 146:Issue 14(2021)
• Page Start: 4595
• Page End: 4604
• Publication Date: 2021-06-23
• Subjects: Chemistry, Analytic -- Periodicals; 543
• DOI: 10.1039/d1an00797a
• Languages: English
• ISSNs: 0003-2654

Abstract

Abstract : A photoelectrochemical enzyme biosensor based on extended-gate field-effect transistor was constructed. Glyphosate was determined sensitively based on acetylcholinesterase inhibition with a detect limit of 3.8 × 10 −16 mol L −1 . Abstract : A new photoelectrochemical enzyme biosensor based on an extended-gate field-effect transistor (EGFET) was constructed for the highly sensitive detection of glyphosate based on the inhibition of acetylcholinesterase (AChE) activity by glyphosate. First, a two-step hydrothermal method was used to introduce ZnO and CdS onto an activated indium tin oxide (ITO) electrode to prepare a CdS/ZnO/ITO electrode. Then, AChE was immobilized on CdS/ZnO/ITO with chitosan to obtain an AChE/CdS/ZnO EGFET sensor. Under optimal experimental conditions, the logarithmic value of glyphosate in the range of 1.0 × 10 −15 –1.0 × 10 −11 mol L −1 exhibited a good linear relationship with the photo-drain current response. The detection limit was 3.8 × 10 −16 mol L −1 (signal-to-noise ratio = 3). The results show that the AChE/CdS/ZnO EGFET sensor has extremely high sensitivity and good selectivity. Moreover, the sensor was used for the determination of glyphosate in vegetables, demonstrating its application for the real-time detection of samples.