ABSTRACT
OBJECTIVE: To establish a Carb/NH2-SPE-GC-MS method for rapid monitoring of 40 kinds of pesticides of four categories in Toddaliae asiaticae (L.) Lam. METHODS: The samples were pretreated with Carb/NH2 solid phase extraction (SPE) subpost, and a GC-MS method was used for the determination of the trace pesticide residues. RESULTS: In comparison with the pesticide residue pretreatment methods included in the Chinese Pharmacopoeia, the Carb/NH2-SPE-GC-MS method showed no significant differences (P>0.05) and was simpler and more feasible in handling a variety of pesticide residues in Toddaliae asiaticae (L.) Lam. Good linearity was obtained for the calibration curves for the 40 kinds of pesticides in the concentration range of 10 to 200 ng·mL-1 (r>0.998 2), the limits of detections (LODs) were around 2.5 ng·mL-1, and the precisions, stabilities and recoveries basically met the methodological requirements. CONCLUSION: Carb/NH2-SPE-GC-MS method established in this paper is simple, rapid, highly sensitive, and accurate for the qualitative and quantitative analysis of multi-component pesticide residues in Toddaliae asiaticae (L.) Lam.
ABSTRACT
OBJECTIVE: To establish a new gas chromatography method coupled with ultrasound-assisted extraction and solid-phase microextraction for rapid analysis of organochlorine pesticide residues (OCPs) in 13 Miao medicines in Guizhou. METHODS: Flos Lonicerae Japonicae was used as an optimization object. Before being analyzed by GC, the sample was extracted by organic solvent and ultrasound, then enriched by SPME. RESULTS: Under the optimized conditions, the linearities of eight kinds of OCPs ranged from 12.5 to 500 ng · g-1, all with good correlation coefficients. The spiked recoveries ranged from 70.4% to 119.8% and relative standard deviations (RSDs) ranged from 8.9% to 14.1%. The detection limits were 1.03-3.45 ng · g-1. CONCLUSION: UAE-SPME-GC method simplifies the preparation steps for traditional Chinese medicines by direct sample enrichment and analysis thus sparing further purification. It is a convenient, environmentally-friendly and rapid method.