Determination of organochlorine pesticide residues in rice by gas chromatography-mass spectrometry following directly suspended droplet microextraction

A simple and efficient approach as directly suspended droplet microextraction ( DSDME ) was applied to the determination of organochlorine pesticides in rice prior to analysis by gas chromatography-mass spectrometry ( GC-MS ). The extraction parameters such as organic solvent type and volume, extraction time, and ion strength were systemically optimized. Furthermore, method linearity, recovery, limits of detections ( LODs ), and precision were also investigated. The proposed method provided good linearity ( R 2 = 0.9900–0.9996). LODs determined by GC-MS in selected-ion monitoring ( SIM ) mode were between 0.0005–0.033 mg/kg. The relative standard deviations ( RSDs ) varied from 2.0–14.0%, while the enrichment factors were between 221–550. The experimental results suggest that DSDME followed by GC-MS is a simple, sensitive, low-cost and little solvent consumption for the determination of organochlorine pesticides in rice, and has high enrichment factors suitable to trace analysis.