Identification of phoxim and omethoate using α-hemolysin nanopore and aptamers

Contamination with pesticides has inflicted substantial harm on human health; therefore, developing rapid, ultra-sensitive, and non-labelling simultaneous detection methods for multiple pesticides is necessary. In this study, we demonstrated that α-hemolysin (α-HL) nanopore sensor can detect and discriminate organophosphorus pesticides of phoxim and omethoate in a single nanopore without requiring labels of the probes or purification of the pesticides in real samples. Aptamers specifically recognise and bind pesticides to obtain pesticide-aptamer complexes that produce characteristic current signals while passing through the nanopore. Phoxim and omethoate were accurately distinguished by a portable instrument within minutes, and their detection sensitivity was up to the femtomole level, whether detected alone or simultaneously. The detection limits of phoxim and omethoate were 8.13 × 10−16 M and 4.16 × 10−15 M. The recoveries of phoxim and omethoate from pear, tomato, and cucumber samples were 82.0–107.0 % and 81.9–118.3 % respectively, with coefficient of variable below 8.0 %. •The α-hemolysin nanopore sensor can detect and discriminate phoxim and omethoate in real samples.•The sensor enables simultaneously detection of phoxim and omethoate within minutes.•The detection limit of the sensor is up to the femtomole level.•The sensor is as reliable and accurate as UHPLC-MS/MS.