Development of deep eutectic solvent based solidification of organic droplets-liquid phase microextraction; application to determination of some pesticides in farmers saliva and exhaled breath condensate samples

Abstract

In the present study, the persistence of some pesticides in the exhaled breath condensate and saliva of farmers who had come into contact with these analytes was monitored using gas chromatography-mass spectrometry. The samples were firstly extracted using a deep eutectic solvent based solidification of organic droplets liquid microextraction method in an extraction device. The device was a U-shaped glass device with a glass filter. The samples were placed in the vessel and the extraction solvent was passed through the filter under a stream of air. In this process the extraction solvent was dispersed in the whole of the solution as tiny droplets and the target analytes were extracted into the droplets. The produced droplets of the extraction solvent were solidified using cool water circulated in the device. The solidified extraction solvent was melted and injected into the determination system. Validation of the method showed limits of detection and quantification at ranges of 2–17 and 10–85 ng L⁻¹ in saliva and 7–59 and 35–295 ng L⁻¹ in exhaled breath condensate, respectively. Real samples, obtained from farmers who had come into contact with the analytes, were analysed and the evidence showed that diazinon and bromopropylate concentrations in EBC samples decreased as the time after spraying increased whereas for the saliva samples the concentrations of analytes increased up to 1.0 h after spraying and then decreased due to their dilution by the excreted saliva and swallowing.