Infrared-enhanced salt-induced homogeneous liquid-liquid microextraction of neonicotinoid pesticides performed in a narrow-bore tube using ionic liquids from fruit juice prior to HPLC-PDA.

In this work, a new and sustainable microextraction technique based on infrared-induced homogeneous liquid-liquid microextraction performed in a narrow-bore glass tube was introduced for the isolation and preconcentration of four neonicotinoid pesticides - namely nitenpyram, acetamiprid, imidacloprid, and thiacloprid-from fruit juices. The method employed an ionic liquid, as an extractant. Phase separation was then triggered by localized heating via an infrared lamp, which was manually passed back and forth along the tube. This thermal input decreased the solubility of the ionic liquid, prompting its releasing and dispersion as fine droplets throughout the aqueous medium. Under the established conditions, the method demonstrated excellent performance including low limits of detection (0.07-0.12 ng mL-1) and quantification (0.23-0.39 ng mL-1), and acceptable extraction recoveries (69-82%). The procedure was successfully applied on different commercial fruit juice samples, in which negligible matrix effects were observed, confirming its reliability in practical applications.