Synthesis and application of new silver and sulfur decorated S-doped reduced graphene oxide in ultra-trace analysis of pesticides by ion mobility spectrometry

In this research study, a novel, facile, and affordable method is presented for the synthesis of a Ag/S/S-RGO nanocomposite. The resulting new nanocomposite was identified by FT-IR, XRD, FESEM, XPS, BET and EDX and employed as a rapid and effective adsorbent with acceptable absorption capacity for the analysis of various pesticides by dispersive solid-phase microextraction combined with ion mobility spectrometry. The main experimental parameters of the method were optimized such as the type of desorption solvent, pH of the sample solution, type of buffer, amount of the sorbent (Ag/S/S-RGO), sorption/desorption time, etc. Under the optimized conditions, linear dynamic ranges of 0.5-110.0, 1.0-110.0, and 0.8-90.0 ng mL-1 were achieved, with limits of detection of 0.25, 0.35, and 0.25 ng mL-1 for simazine, alachlor, and haloxyfop, respectively. The relative standard deviations (RSD%) were obtained as <5.0%. Eventually, the method was utilized for the simultaneous determination of simazine, alachlor, and haloxyfop in environmental and agricultural samples with recoveries between 95.0 and 104.6%.