A porous composite sorbent incorporating a metal organic framework and zinc oxide in cryogel to extract carbamate pesticides

Abstract

A highly porous composite sorbent was designed and fabricated by incorporating of a metal organic framework (MOF); Materials of Institute Lavoisier (MIL-101) and zinc oxide (ZnO) into polyvinyl alcohol (PVA) cryogel. The composite sorbent was produced specifically to extract four carbamates (carbofuran, carbaryl, isoprocarb and diethofencarb) designed to be applied in syringe solid phase extraction (SPE). MIL-101 and ZnO can enhance the adsorption efficiency of carbamate pesticides by creating ?-? stacking and hydrogen bonding, while porous PVA cryogel was utilized as a solid support which helped to reduce back pressure of the system. Different variables influencing the target analytes extraction efficiency include amount of MIL-101 and ZnO, desorption conditions, sample pH, ionic strength, sample flow rate and sample volume were optimized. The developed porous composite sorbent exhibited extraction ability of carbamates linearly ranging from 1.0 to 150.0 ?g L?1 for all target carbamate pesticides with the limit of detection 0.3 �g L-1. The method was successfully utilized to identify carbamates in fruit juice and white wine with obtaining decent recoveries from 78.1 to 108.2 %. The developed composite sorbent has a good accuracy, simple to fabricate, works rapidly and able to be reused to provide high extraction-regeneration cycles.

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