Vacuum-assisted headspace-solid phase microextraction of pesticides in grape samples

Abstract

Vacuum-assisted headspace solid-phase microextraction (Vac-HS-SPME) could provide an alternative for extracting pesticides from grape samples. Vac-HS-SPME method is utilized to the simultaneous analysis of six pesticides from various classes, namely boscalid, quizalofop-p-methyl, oxyfluorfen, fluroxypyr-meptyl, metribuzin and epoxiconazole. In this study investigated and optimized the impact of independent variables, such as extraction temperature, extraction time, fiber coating, incubation time, salt effect, sample volume, air evacuation time, pH, desorption time with the objective of achieving lower detection limits (ranging from 0.11 to 0.61 µg mL-1) and effective analyte responses. Moreover, in this work a comparison was made between classical solid phase microextraction and vacuum-assisted solid phase microextraction for the extraction of pesticides in grape samples under the same parameters. The results clearly demonstrated that the combination of Vac-HS-SPME proved to be more appropriate and selective for the extraction of pesticides from grape samples.

Keywords

• Vacuum-assisted headspace solid-phase microextraction
• Pesticide residues
• Gas chromatography
• Mass spectrometry
• Analytical performance
• Carbowax-polyethylene glycol