Currently, the main sample pretreatment methods for forensic toxic analysis are liquid-liquid extraction （LLE） and solid-phase extraction （SPE）. As a simple, convenient, and low-cost LLE method, dispersion liquid-liquid microextraction （DLLME） has high enrichment factor and good extraction efficiency, and therefore has attracted the attention of many researchers in the field of toxicology analysis in recent years. As a multi-functional microextraction method, DLLME has been widely used in the analysis of pesticides, sleeping sedatives, drugs and heavy metal poisons in forensic toxic analysis. Meanwhile, it can also be used in combination with such a variety of analytical instruments as gas chromatography-electron capture detectors （GC-ECD）, high performance liquid chromatography-diode array detectors （HPLC-DAD）. As a sample pretreatment method, DLLME has the advantages of simple operation, less use of organic solvent, reliable results and good reproducibility, thus can meet the requirements of modern court toxic analysis.
Forensic Toxicology ; Liquid Phase Microextraction ; Reproducibility of Results ; Solid Phase Extraction ; Solvents

Objective To establish a method for determination of escitalopram in biological samples by ultrasound-assisted ionic liquid-dispersive liquid-liquid microextraction combined with gas chromatography-tandem mass spectrometry （GC-MS/MS） and provide evidences for forensic determination of cases related to escitalopram. Methods The 1-hexyl-3-methylimidazolium hexafluorophosphate （[C₆MIM][PF₆]） was selected as an extract solvent to process biological samples. Ultrasound-assisted extraction was used on the samples. Then the samples were detected by GC-MS/MS. Results The linear range of escitalopram in blood and liver were 5.56-1 111.10 ng/mL and 0.025-5.00 mg/g, respectively. The correlation coefficient （r） were greater than 0.999, limit of detection （LOD） were 4.00 ng/mL and 2.00 μg/g, limit of quantitation （LOQ） were 14.00 ng/mL and 6.00 μg/g, respectively. The extraction recovery rates were all greater than 50%, the interday and intraday precision were less than 20%. Escitalopram was detected in blood and liver samples from the actual poisoning case by this method with a content of 1.26 μg/mL and 0.44 mg/g, respectively. Conclusion The ultrasound-assisted ionic liquid-dispersive liquid-liquid microextraction combined with GC-MS/MS is environment friendly, rapid, has good enriching effect and consumes less organic solvent and can be used for forensic determination of escitalopram related cases.
Citalopram ; Gas Chromatography-Mass Spectrometry ; Limit of Detection ; Liquid Phase Microextraction ; Tandem Mass Spectrometry

The current methods to prepare and determine pesticide residues in Chinese herbal medicine were summarized in this paper. In addition,the new techniques to prepare and determine pesticide residues used in recent years was reviewed, which included solid-phase micro-extraction (SPME) , supercritical fluid extraction ( SFE) , accelerated solvent extraction (ASE) , immune affinity chromatography (IAC), supercritical fluid chromatography (SFC), column switching high performance liquid chromatography (CSHPLC), high performance liquid chromatography/mass spectrometry (HPLC/MS), capillary electrophoresis (CE) and capillary zone electrophoresis (CZE) , and immune analysis (IA), etc. To sum up, these would bring a great progress in analysis of the pesticide residues in Chinese herbal medicine, and make it more rapidly, accurately and normatively.
Chromatography, High Pressure Liquid ; Chromatography, Supercritical Fluid ; Drugs, Chinese Herbal ; chemistry ; Electrophoresis, Capillary ; Gas Chromatography-Mass Spectrometry ; Pesticide Residues ; analysis ; isolation & purification ; Plants, Medicinal ; chemistry ; Reproducibility of Results ; Solid Phase Microextraction ; Technology, Pharmaceutical ; methods