Sensitive and rapid electrochemical detection of nitroaromatic pesticides by the ordered macro-microporous ZIF-8 immobilized lipase-based sensor

The high toxicity and bioaccumulation effects of nitroaromatic pesticides and their serious environmental risks have led to a sharp increase in public concern about pesticide residues. Present work developed a direct, rapid, sensitive and reliable Candida rugosa lipase (CRL)@ the ordered macro-microporous ZIF-8 (MAC-ZIF-8) nanofibers biosensor (CRL@MAC-ZIF-8 nanofibers) for methyl parathion and chlornitrofen residues detection in lake water. The biosensors fabricated by the CRL@MAC-ZIF-8 nanofibers demonstrated wide linear range for both methyl parathion (0.5-114 & mu;M) and chlornitrofen (1-40 & mu;M) detection. The biosensors also demonstrated good reusability for methyl parathion detection with retainment of more than 97% of its initial response after scanning continuously for 100 times. During 1 month storage stability test at 4 degrees C, the fabricated biosensor demonstrated excellent stability for methyl parathion detection with retainment of 86%-100% of its initial response. Meanwhile, the biosensors also demonstrated good recovery rates when the biosensors were used to detect methyl parathion and chlornitrofen residues in lake water sample.