Solid-phase extraction of organophosphates from polluted waters on a matrix-imprinted sorbent

The study aims to synthesize a selective matrix imprinted sorbent for the extraction of parathion and malathion. The structural unit of the polymeric framework was 2-methylpropanoic acid, the intermolecular crosslinker was ethylene glycol dimethacrylate, the polymerization initiator was azobisisobutyronitrile, the porogen was xylene, and the analyte was parathion. The synthesis was carried out under conditions of heating the reaction mixture to 65 °C, after which the matrix was washed with methanol to remove the analyte. For comparison purposes, non-imprinted control polymer was used as a negative control, which was prepared similarly, but without the addition of the analyte. The identification and quantification of organophosphates were performed by gas chromatography, and the morphological characteristics of the sorbents were evaluated by scanning electron microscopy. The optimal buffer for the purification of organophosphates was acetate buffer with a pH of 4; the optimal organic eluent was methanol. The limit of detection for para- and malathion was 0.1 μg/ml; the limit of quantification was 0.3 μg/ml. Linearity in the extraction conditions was observed in the range of 0.1–1 μg/ml for parathion and 0.1–2 μg/ml for malathion. The developed method will enable quick, selective, and cost-effective extraction of organophosphates from various substrates.