Phthalocyanine-containing polymer derived porous carbon as a solid-phase extraction adsorbent for the enrichment of phenylurea herbicides from water and vegetable samples

In this study, a porous carbon was prepared by the carbonization of a phthalocyanines-containing polymer. The carbon material was characterized by using scanning electron microscope, transmission electron microscope, X-ray diffraction and N 2 adsorption–desorption isotherms. The material was used as the solid phase extraction adsorbent for the enrichment of five phenylurea herbicides (monuron, monolinuron, isoproturon, chlortoluron, and buturon) from water and vegetable samples prior to high performance liquid chromatographic analysis. Under the optimized conditions, a good linearity for the analytes existed in the range of 0.1–80.0 ng/mL for water samples, 0.5–80.0 ng/g for white turnip samples, and 0.2–80.0 ng/g for cucumber samples, with determination coefficients of 0.9987–0.9998. The limits of detection for the five analytes at a signal to noise ratio of 3 were 0.01–0.02 ng/mL for water, 0.05–0.10 ng/g for white turnip and 0.03–0.05 ng/g for cucumber. The limits of quantification at the signal to noise ratio of 9 were 0.03–0.06 ng/mL for water, 0.15–0.3 ng/g for white turnip, and 0.1–0.15 ng/g for cucumber.