Zhai_2020_J.Sci.Food.Agric__

BACKGROUND: Increased awareness of consumers on food safety promotes the development of rapid and sensitive detection techniques for pesticide residues. In this study, a new type of rapid detection card for organophosphorus (OPs) and carbamates (CMs) pesticide residues was developed by electrospinning. The card involved enzyme fiber mat (EFM) and substrate fiber mat (SFM) which were prepared by mixing poly(vinyl alcohol) (PVA) with acetylcholinesterase (AChE) and indolyl acetate (IA), respectively. RESULTS: The mean diameter of fibers was 240+/-53 nm for EFM and 387+/-84 nm for SFM. Results of ATR-FTIR and XPS confirmed that AChE and IA were successfully encapsulated into the fibers. The minimum concentrations of AChE and IA for effective detection were 1 mg/mL and 3 mg/mL, respectively, and the optimal detection time was 15 min. The limits of detection for this card were 0.5 mg/L for omethoate, 1.5 mg/L for malathion, 0.1 mg/L for carbaryl, and 0.02 mg/L for carbofuran. The detection card exhibited good storage stability and its activity can be maintained when stored at room temperature for at least 4 months. Additionally, the EFM can be reused for three times. CONCLUSION: The detection card obtained here was superior to the commercial card in detecting pesticide residues in the real food samples. Hence, this electrospun detection card is potential for simple, rapid and sensitive analysis of pesticide residues. This article is protected by copyright. All rights reserved.