Ionic liquid-derived magnetic mesoporous carbon as a new magnetic sorbent for solid-phase extraction of triazine herbicides in water samples

Triazine herbicides are one of the most widely used herbicides and have caused much concern about their toxic effects on human and ecosystem. Their wide application may cause pollution to soil, crops, surface water and other drinking water sources due to their large dosage, stable chemical property, long residue time and higher water solubility [۱-۲]. In the present work, a new and efficient method for ultra-trace determination of triazine herbicides in water was developed, using magnetic mesoporous carbon-based solid-phase extraction, followed by high performance liquid chromatography determination. The sorbent was synthesized using an imidazolium-based ionic liquid as the carbon source, guanine as the nitrogen source, FeCl۳ as the iron source, and SBA-۱۵ as the hard template. The effects of sample pH, extraction time, type and volume of elution solvent and extraction solvent, desorption time, and salt addition on the extraction efficiency of atrazine were examined and optimized. Under the optimum conditions, the LODs, LOQs, and, LDR were in the range of ۰.۰۸–۰.۳۴ ng mL−۱ and ۰.۲۵–۱.۱۴ ng mL−۱, ۰.۲۵-۱۰۰ ng mL−۱, respectively. The developed method was applied to the determination of triazine herbicides in river and lake samples, with RSD of ۲.۹–۱۰.۵%. Therefore, the proposed method allows proper monitoring of trace triazine herbicides in various environmental waters.