Combination of nano-onion-based dispersive solid phase extraction combined with deep eutectic solvent-based dispersive liquid-liquid microextraction for trace analysis of pesticides

Combination of carbon nano onions-based dispersive solid phase extraction with deep eutectic solvent-based dispersive liquid-liquid microextraction was utilized for the extraction of some pesticides from fruit juice and vegetable samples. For this purpose, the carbon nano-onions were prepared from castor oil using a flame-assisted pyrolysis method. The nanoparticles were added into the sample solution containing the analytes to extract them. In the following, the analytes were concentrated into a few microliters of choline chloride: decanoic acid: catechol deep eutectic solvent using the microextraction procedure to obtain high enrichment factors. The results showed low limits of detection (0.5-1.0 ng/mL) and quantification (1.8-3.2 ng/mL) with a satisfactory linearity for three orders of magnitude (r(2) > 0.994). The precision of the developed method expressed as relative standard deviations was good (<= 6.9 %). The method provided high enrichment factors (335-430) and extraction recoveries (67-86 %). Finally, the selected pesticides were analyzed in two fruit juices and four vegetable samples successfully.

Automated summary

A combined method of carbon nano onions-based dispersive solid phase extraction with deep eutectic solvent-based dispersive liquid-liquid microextraction was developed for the extraction of pesticides from fruit juice and vegetable samples. The method showed low limits of detection, good linearity, and high extraction recoveries.