Sol-gel hybrid cyanopropyltriethoxysilane-methyltrimethoxysilane as adsorbent for dispersive-micro solid phase extraction of selected organophosphorus pesticides in water samples

Abstract

Commercial solid phase extraction (SPE) sorbents normally used for organophosphorus pesticides (OPPS) analysis is C18. However, it show low retention for polar compounds and is rather expensive. The limitations are overcome through the development of a new sol-gel hybrid material, cyanopropyltriethoxysilane-methyltrimethoxysilane (CNPrTEOS-MTMOS). Sol-gel hybrid CNPrTEOS-MTMOS was successfully synthesized and applied as an adsorbent for dispersive-micro-SPE (D-μ-SPE) of three selected OPPs from several water samples. Extracted analytes were analyzed using gas chromatography-mass spectrometry. Under the optimum conditions (100 mg CNPrTEOS-MTMOS as adsorbent, 10 mL water samples, 7 min extraction time, 300 μL methanol as desorption solvent and 3 min desorption time), the method showed excellent detection limits (0.01-0.004 μg L−1 at S/N = 3) and linear range achieved were 0.01-10 μg L−1. The CNPrTEOS-MTMOS sorbent offers an alternative sorbent material for the extraction of OPPs of various polarity. The developed D-μ-SPE method was successfully applied for the simultaneous analysis of OPPs in several water samples and results were compared with published results. Sol-gel hybrid CNPrTEOS-MTMOS showed high potential as an alternative adsorbent for D-μ-SPE technique for OPPs.