Carbon black-assisted miniaturized solid-phase extraction of carbamate residues from ginger by supercritical fluid chromatography combined with ion mobility quadrupole time-of-flight mass spectrometry

Abstract

In this study, the qualitative and quantitative analysis of carbamate pesticide residues was achieved by a miniaturized solid phase extraction (SPE) method and supercritical fluid chromatography (SFC) combined with ion mobility quadrupole time-of-flight mass spectrometry (IM-Q-TOF/MS). The target compounds in real samples were enriched using the miniaturized SPE method, and the parameters affecting enrichment efficiency were evaluated with the optimal enrichment conditions as follows: carbon black (20 mg) and methanol used as the elution solvent with a volume of 200 µL. Meanwhile, the back temperature, back pressure and make-up solvent in SFC were investigated, and the corresponding optimal conditions were 60 °C, 140 bar and methanol with 0.1% formic acid, respectively. Subsequently, accurate mass values of nine carbamate pesticides were identified by IM-Q-TOF/MS. Through method validation and sample analysis, the results indicated that satisfactory validation parameters, such as linearity (R2 > 0.99), limit of detection (<7.01 ng/mL), limit of quantitation (<23.36 ng/mL), precision (0.21–3.91%) and reproducibility (0.08–4.76%), were obtained. Finally, this method was successfully applied to the enrichment and detection of carbamate residues in real samples of ginger.