Silica aerogel modified electrospun polyacrylonitrile as a sorbent for thin-film microextraction of chlorpyrifos from real samples coupled with corona discharge ion mobility spectrometry detection.

In this paper, modified polyacrylonitrile/silica aerogel fibers were prepared and used as an adsorbent for thin-film microextraction of chlorpyrifos. The extracted analyte was analyzed by corona discharge ion mobility spectrometry. The electrospinning method was applied for the preparation of polyacrylonitrile fibers. The alkaline hydrolyzation technique was used to modify the electrospun film surface. Silica aerogel was synthesized on the surface of modified electrospun polyacrylonitrile fibers by the in situ growth technique. To access a high extraction yield, effective synthesis and extraction parameters such as NaOH concentration, reaction temperature and time, thin-film pretreatment, gelation time, solution pH, ionic strength, and extraction time were studied. The linearity range and the limit of detection of the method were 1-100 µg L-1 and 0.3 µg L-1, respectively. The precision of the method was 4 and 12% for the concentration levels of 5 and 60 µg L-1, respectively. Chlorpyrifos was successfully determined by the method in well water, river water, agricultural wastewater, and tangerine samples.