Preconcentration and determination of organochlorine pesticides in seawater samples using polyaniline/polypyrrole-cellulose nanocomposite-based solid phase extraction and gas chromatography-electron capture detection

摘要

In this work, the chemically modified filter paper with polyaniline/polypyrrole (PANI/PPY), denoted as PANI/PPY/cellulose nanocomposite, was prepared and used as the solid phase extraction (SPE) sorbent for preconcentration and extraction of some organochlorine pesticides (OCPs) in natural water samples. The proposed sorbent was also characterized with scanning electron microscopy (SEM) and exhibited that globular polymers could incorporate into the cellulose fibers of the paper sheet. Several experimental parameters related to the preconcentration of OCPs on the coated filter paper were also examined. The experimental results showed that the PANI/PPY coated filter paper could extract OCPs with relatively high enrichment factors. The evaluation also exhibited a dynamic range of 5-250 μg L-1 for OCPs with proper correlation coefficient (R2). The limit of detections of heptachlor, aldrin, dieldrin, endrin and 4-dichlorodiphenyltrichloroethane (4-DDT) were found to be 0.39, 0.28, 0.47, 0.51 and 0.31 μg L-1, respectively. The proposed method was also applied for analysis of OCPs in seawater sample and the recoveries of analytes were in the range of 77.4 to 102.7 %.