RESUMO
The sensitive detection of iprobenfos (IBF) and edifenphos (EDI) was successfully conducted by using a new aptamer-based colorimetric multi-aptasensor. The dissociation constants of this multi-target aptamer to both iprobenfos and edifenphos were found to be 1.67 µM and 38 nM, respectively, according to the isothermal calorimetry assay. The aptamer EIA2 was selective to only IBF and EDI, confirmed by AuNP assays. By using this multi-aptasensor, both pesticides IBF and EDI can be eventually detected in a range from 10 nM to 5 nM, respectively. This multi-aptasensor was successfully implemented in spiked rice samples and the accuracies of this AuNP-based multi-aptasensor were around 80 and 90% in spiked paddy and polished rice samples, respectively. This aptamer EIA2 could be applied not only for the detection of pesticides from real samples in agriculture field as POC, but also can be used as a bioreceptor for other types of aptasensors.
