Given the complexity of biological samples and the trace nature of target materials in forensic trace analysis, a simple and effective method is needed to obtain sufficient target materials from complex substrates. Magnetic nanoparticles (MNPs) have shown a wide range of application value in many research fields, such as biomedicine, drug delivery and separation, due to their unique superparamagnetic properties, stable physical and chemical properties, biocompatibility, small size, high specific surface area and other characteristics. To apply MNPs in the pretreatment of forensic materials, maximize the extraction rate of the target materials, and minimize interference factors to meet the requirements of trace analysis of the target materials, this paper reviews the application of MNPs in the fields of forensic toxicological analysis, environmental forensic science, trace evidence analysis and criminal investigation in recent years, and provides research ideas for the application of MNPs in forensic trace analysis.
Magnetite Nanoparticles/chemistry* ; Forensic Medicine ; Forensic Sciences ; Forensic Toxicology

Biological matrix reference material is a reference material that combines the target material with the biological matrix. The biological matrix reference material has higher consistency with the authentic specimens in forensic toxicology, and its application has a positive effect on improving the accuracy of test results. This paper reviews the research on the matrix reference materials corresponding to three common biological test materials (blood, urine and hair). In order to provide reference for the development and application of biological matrix reference materials in forensic toxicology, this paper mainly introduces the research progress of preparation technology of biological matrix reference materials and some existing products and their parameters evaluation.
Forensic Toxicology/methods* ; Hair ; Body Fluids

In recent years, zebrafish model has been widely concerned and recognized by scholars at home and abroad. As an animal model, zebrafish is of great research value because it is easy to feed, easy to operate, observe and analyze, and the model results can be highly combined with human body test data. Zebrafish model has been widely used in many fields, including basic medical science, clinical medicine, agricultural production, environmental toxicology and forensic science. This review introduces the biological characteristics of zebrafish, summarizes the research progress of zebrafish model in toxicology, and discusses the application prospect of zebrafish model in forensic science.
Animals ; Forensic Sciences ; Forensic Toxicology ; Humans ; Zebrafish

Mass spectrometry imaging （MSI） is a new imaging technology that can simultaneously detect and record the spatial distribution information of multiple molecules on the sample surface without labeling. The main principle of MSI is to combine mass spectrometry with imaging technology and irradiate the sample slice with ion beam or laser to ionize the molecules on its surface, obtain the mass spectrometry signal through the detector, convert the obtained data into pixel points by the imaging software, and then construct the spatial distribution image of the target compound on the tissue surface. The sample preparation for MSI include： sample collection and storage, tissue section, tissue pretreatment, selection and application of matrix. At present, this technology has been widely used in the fields of biomedicine, new drug development and proteomics, and its application in the field of forensic toxicology has also gradually attracted attention. This article reviews the principles and sample preparation process of MSI, describes the application of MSI in abused substances and metabolites of various material matrices, herbal mixtures, latent fingerprints, hair and animal and plant tissues, and discusses the prospects of the application of this technology in forensic toxicology, in order to provide ideas and references for the application of MSI technology in forensic toxicology.
Animals ; Diagnostic Imaging ; Forensic Toxicology ; Humans ; Mass Spectrometry ; Plants ; Proteomics ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

Chloroquines are the long-established prescription drug, which are often used clinically to treat malaria and connective tissue diseases. Since December 2019, corona virus disease 2019 （COVID-19） outbreaks caused by 2019 novel coronavirus （2019-nCoV） has occurred in China and many countries around the world. Due to the lack of drugs against COVID-19, the disease spreads rapidly and the mortality rate is relatively high. Therefore, specific drugs against 2019-nCoV need to be quickly screened. The antimalarial drug chloroquine phosphate which has already been approved is confirmed to have an anti-2019-nCoV effect and has been included in diagnostic and therapeutic guidelines. However, awareness of the risk of chloroquine phosphate causing acute poisoning or even death should be strengthened. The current dosage recommended in clinical treatment is larger than that in previous treatment of malaria and the period of treatment is longer. Many provinces have required close clinical monitoring of adverse reactions. This paper reviews the pharmacological effects, poisoning and toxicological mechanisms, in vivo metabolism and distribution, and forensic issues of chloroquine drugs, in order to provide help to forensic practice and clinical work.
Betacoronavirus ; COVID-19 ; China ; Chloroquine/therapeutic use* ; Coronavirus Infections/drug therapy* ; Forensic Toxicology ; Humans ; Pandemics ; Pneumonia, Viral/drug therapy* ; SARS-CoV-2 ; COVID-19 Drug Treatment

Objective To establish an analysis method for simultaneous determination of 13 sedative substances and their metabolites in blood by liquid-liquid extraction and liquid chromatography-tandem mass spectrometry （LC-MS/MS） technology and to apply the method to actual cases. Methods The samples were extracted with ethyl acetate after an internal standard was added. The extract was condensed until it was nearly dry and then its residues were dissolved with methanol, filtered through 0.22 μm filter and finally determined. The 13 sedative substances and their metabolites were separated through the C₁₈ chromatographic column, then gradient elution was performed on them with methanol and 20 mmol/L ammonium formate （containing 0.1% formic acid） solution. After that, they were determined in the electrospray positive ion mode and quantified by internal standard method. Results The 13 sedative substances and their metabolites in blood showed good linearity in the range of 5-200 μg/L with correlation coefficients ranging from 0.990 3 to 0.999 8. The detection limits were 0.1-1.0 μg/L. Recovery rates of sedative substances were in the range of 71.2%-93.4% when solutions with concentrations of 10, 50 and 200 μg/L were added. The deviations of intra-day and inter-day relative standard deviations （RSD） were not more than 8.6%. Accuracies （bias） were within ±9.8%. Conclusion This method is rapid, simple, effective and sensitive, and can be applied to analysis of 13 sedative substances and their metabolites in blood in forensic toxicology.
Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Forensic Toxicology ; Hypnotics and Sedatives ; Tandem Mass Spectrometry

Metabolomics is an interdisciplinary subject that rose in the post-genomic era, which focuses on quantitative study of the response of living organisms to outside stimulation and pathophysiological changes, as well as multiple dynamic response of the level of in vivo metabolites caused by genetic mutation. It is extensively used in basic research of system biology, materia medica, clinical medicine, etc. In the forensic field, metabolomics mainly focuses on forensic toxicology, but with the generalization of certain techniques, it's foreseeable that metabolomics has a broad research prospect in forensic pathology. This article summarizes the major analysis techniques and methods of metabolomics, describes the research status of metabolomic techniques in the field of forensic pathology application research, including postmortem interval and death cause. Moreover, this article summarizes and discusses the potential applicable areas, in order to provide reference for relative research and application.
Autopsy ; Forensic Pathology/trends* ; Forensic Toxicology ; Humans ; Metabolomics ; Postmortem Changes

Amphetamines are chemical synthetic drugs that are becoming increasingly popular in China. As a common sample in the inspection of poisons, hair has the advantages of easy storage, good stability, and long detection time compared with traditional human body fluid samples （blood, urine）, thus possesses an unique application value in the field of forensic toxicology analysis. By now, methods for detecting amphetamines in human hair have been widely used, and validity of the results has been recognized and adopted by the court. This paper reviews domestic and foreign research progress of the detection of amphetamines in hair samples, including the pretreatment and analytic methods.
Amphetamines/analysis* ; China ; Forensic Toxicology ; Hair/chemistry* ; Humans ; Substance Abuse Detection

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 an ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） rapid determination method for simultaneous analysis of 20 fentanyl-related substances in blood. Methods With fentanyl-D₅ as an internal standard, the blood was extracted by liquid-liquid extraction （LLE）, then separated with an ACQUITY UPLC HSS T₃ chromatographic column, and finally 20 fentanyl-related substances were simultaneously analyzed with multiple reaction monitoring （MRM） mode. Results The limits of detection （LOD） of all compounds were 0.02-0.03 ng/mL, and the limits of quantitation （LOQ） were 0.05-0.2 ng/mL. Within the mass concentration range of 0.05-40 ng/mL, 20 fentanyl-related substances had a good linear relationship, and correlation coefficients were larger than 0.99. The accuracy of the method was 87.69%-114.68% and the extraction recovery rate was 85.35%-101.80%, and no significant matrix effect was observed. The established method was successfully applied to the detection of sufentanil in rat blood after sufentanil was injected. Sufentanil could still be detected in blood of rats 10 h after sufentanil injection. Conclusion The established method has the advantages of simple pretreatment, high sensitivity and good selectivity, and can be used for the determination of fentanyl-related substances in forensic toxicology analysis.
Animals ; Chromatography, High Pressure Liquid ; Fentanyl/blood* ; Forensic Toxicology ; Rats ; Reproducibility of Results ; Sufentanil/blood* ; Tandem Mass Spectrometry