Application of an optimized dispersive nanomaterial ultrasound-assisted microextraction method for preconcentration of carbofuran and propoxur and their determination by high-performance liquid chromatography with UV detection

An extractionmethod based on dispersive nanomaterial ultrasound-assisted microextraction was used for the preconcentration of carbofuran and propoxur insecticides in water samples prior to high-performance liquid chromatography with UV detection. ZnS: Ni nanoparticles were synthesized based on the reaction of the mixture of zinc acetate and nickel acetate with thioacetamide in aqueous media and then loaded on activated carbon (ZnS: Ni-AC). Different methods were used for recognizing the properties of ZnS: Ni-AC and then this nanomaterial was used for extraction of carbamate insecticide as new adsorbent. The influence of variables on the extraction method (such as amount of adsorbent (mg: NiZnS-AC), pH and ionic strength of sample solution, vortex and ultrasonic time (min), ultrasound temperature and desorption volume (mL) was investigated by a screening 2(7-4) Plackett-Burman design. Then the significant variables were optimized by using a central composite design combined with a desirability function. At optimum conditions, this method had linear response > 0.0060-10 mu g/mL with detection limit 0.0015 mu g/mL and relative standard deviations < 5.0% (n = 3).