The determination of phoxim in cadaveric material by gas-liquid chromatography]

The developed gas-liquid chromatographic procedure for forensic chemical detection and measurement of phoxim in cadaveric material permits the detection in 25 g of an organ of 44 to 52% of added phoxim. The threshold of phoxim measurement in 100 g of the liver is 0.04 mg, the least volume of phoxim detectable being 0.02 g. The developed gas-liquid chromatographic technique should be used as an additional method together with thin-layer chromatography, for a more objective evaluation of the results of forensic chemical analysis of cadaveric material for phoxim.     

Detection of chlorinated carbohydrates in putrefactive biological material

Carbochlorohydrates were separated from putrefaction products of organic substances and volatile solvents by gas chromatographic column packed with CaA 5 A. A 100 x 0.4 cm column, used for forensic chemical analysis of fresh and putrefactive cadaveric material, proved to be highly effective. The data were confirmed by results of chemical analysis of distillates from the viscera.     

Immunochemical methods in detection of opiates in tissues and organs

Conditions of isolation of opiates from tissues and analysis of the resultant extracts by immunochemical methods are discussed. The main characteristics of OPIATES U kits (Pharmatech) for polarization fluorescent immunoanalysis of cadaveric material (liver) are determined. Immunochemical methods for forensic chemical analysis for opiates are experimentally compared.     

ELISA-based determination of opiates in purulent transformation of cadaveric material

Abuse of drugs has been a topical issue up to the present-day. Opiates like morphine and heroin are still prevalent. The routine methods of determination of drugs in blood made within the forensic medical expertise are time-consuming and samples must be specially prepared for them. ELISA, when used for the determination of opiates in blood and urine, significantly cuts the test time. According to our research results, the diagnosis of opiates by ELISA is advisable at the preliminary stage of the forensic expertise of cadaver; the method is informative, which is of extra importance in cases of purulent transformation of cadaveric material.     

Detection of 1,4-benzodiazepine derivatives in liver tissues by immunochemical methods

The possibility of using immunochemical methods in general forensic chemical analysis of cadaveric material for narcotics is demonstrated. Conditions of isolation of 1,4-benzodiasepines from tissues and analysis of the resultant tissue extracts by polarization fluoroimmunoassay (PFIA) and solid-phase enzyme immunoassay are described. Time course of concentrations in tissue extracts stored for a long time has been studied by PFIA. Characteristics of Benzodiazepines Serum kits (Abbott) for PFIA of liver extracts are determined.     

Determination of clofelin in blood by gas chromatography-mass spectrometry

Gas chromatography--mass spectrometry is proposed for measuring clofelin (clonidine) in cadaveric blood. The method includes liquid-liquid extraction of clonidine from the blood, derivatization with pentafluorobenzyl bromide, and subsequent purification of derivatization products before chromatographic analysis. The range of 0.5-50.0 ng/ml covers therapeutic and lethal concentrations of clonidine in the blood. The method was tried on expert material in Chelyabinsk Regional Bureau of Forensic Medical Expert Evaluations and can be used in forensic chemical and toxicological analysis.     

The determination of chromium in cadaveric material by using cyclohexanecarboxylic acid

Method of chrome detection in the course of forensic chemical investigation in the cadaveric material on the basis of cyclohexan-carbonic acid use is presented. Results of experimental researches showed efficacy of method tested as compared to the common one. Method suggested can be used in laboratory conditions to extract chrome from visceral organs of human cadaver.     

Method of determining methemoglobin in cadaver blood

Poisoning with methemoglobin toxins are not rare in forensic medical practice, but there is still no reliable method for measuring methemoglobin in cadaveric biological fluids and tissues. The author investigated factors affecting evaluation of natural amounts of methemoglobin in the blood, compared several methods for methemoglobin measurements, and developed qualitative characteristics indicating the presence of methemoglobin in cadaveric blood. A rational method for measuring methemoglobin in the blood, blood clots, and tissues is offered for forensic chemical and biochemical evaluations.     

Illuminating the benefits and limitations of forensic light sources

Forensic light sources, such as a Crime-lite, are used in forensic laboratories and by police staff in the examination for, and detection of, biological material. Whilst the benefits of using forensic light sources are relatively well understood, their limitations are less-so. This report details the outcome of studies, validation and review by three forensic laboratories, as well as three case examples, to highlight both the strengths and weaknesses of the tested forensic light sources and to demonstrate that, whilst a useful preliminary screening tool, they should not be used in isolation without subsequent presumptive chemical testing. False positives and negatives are common, and the background substrate and specific biological material present can have a significant effect on the outcome of examination when using a forensic light source.     

Detection of Contact Traces of Powdery Substances

The current practice in securing the contact traces of chemical substances taken from clothes belonging to a person suspected of manual handling explosives is focused on pockets and cuffs. The outerwear worn by people who had contact with fluorescent powders that simulate explosives and drugs was the subject of this study. Clothes were first exposed to the test substance for a period of time and then analyzed by fluorescence methods to determine the location of the highest quantity of traces. The results obtained from the study confirm that the areas with the highest concentration of powdery traces are different from those suggested by current forensic practice. They appear to be promising for a more efficient identification of the suspects involved in illegal manufacturing of drugs of abuse or explosives. Moreover, they may be helpful for developing the methodology for handling the evidence material in the forensic clothing examination process.     

Gas chromatography with mass-selective detector in testing blood for amitriptyline and nortriptyline

The article describes the method of simultaneous detection of amitriptiline and nortriptilin in cadaveric blood using gas chromatography with mass-selective detection. Preparation includes liquid-liquid extraction and derivation with trifluoroacetic anhydride. Nortriptilin threshold of detectability in the blood is 0.02 mcg/ml, amitriptilin one--0.05 mcg/ml. The range of detectability--0.05-3.0 mcg/ml for both compounds. Maximal error of the compounds detectability was under 12.9% for concentrations 0.10 mcg/ml and 10.6% for concentrations 2.0 mcg/ml. The method was tested on expert material in forensic chemical examinations.     

Forensic medical characteristic of the thermal injury caused by inflammation of combustible fluids

The diagnostics of thermal injuries caused by inflammation of combustible fluids should be based on the comprehensive assessment of the results of examination of the scene of the accident, autopsy studies, forensic chemical expertise, and analysis of the circumstances of the case and/or medical documentation. Special attention should be given to the choice of adequate methods for taking samples to be used in forensic chemical studies. The assessment of thermal injuries caused by inflammation of combustible fluids must take into consideration the time and conditions under which they were inflicted (e.g. closed or open space, vertical or horizontal position, etc.).     

The use of the expert BIO-RAD REMEDi HS Drug Profiling System in forensic chemical analysis

Urgent toxicology expert BIO-RAD REMEDi HS Drug Profiling System can be used for forensic chemical analysis of biological fluids extracted from biological material and viscera as a tentative test.     

Sub-sampling and preparing forensic samples for pollen analysis

The main forensic application of palynology is in providing associative evidence, assisting to prove or disprove a link between people and objects with places or with other people. Although identification and interpretation of pollen is a specialist job, sub-sampling and preparing pollen samples for analysis may be carried out by non-specialists. As few forensic laboratories have residing palynologists, laboratories may wish to reduce the cost of analysis or risk of contamination by doing their own sub-sampling and preparation. Presented is a practical guide for sub-sampling and preparing forensic samples for pollen analysis, providing a complete standard procedure for both the palynologist and non-specialist. Procedures for sub-sampling include a wide variety of materials commonly collected for forensic analysis (soil, clothing and other fabrics, footwear, twine and rope, firearms, granulated materials, plant and animal material, and illicit drugs), many of which palynologists will not be familiar with. Procedures for preparation of samples (pollen concentration) are presented as a detailed, step-by-step method. Minimizing the risks of laboratory and cross-sample contamination during sub-sampling and preparation is emphasized.     

毛发中毒品分析

毛发分析在法庭毒品分析领域有其独特的优势,很多国家的法化学实验室,毛发分析已成为毒品检测的常规操作,并已得到了法庭的承认、采纳。本文对毒品进入毛发的机制、毛发的现场勘查、毛发中毒品分析程序、毛发中毒品分析结果的评判进行了综述。简单地介绍了毛发在现场勘查中采取、包装、送检的基本方法和技术人员在操作过程中的注意事项,以及针对毛发检验中的特殊技术处理;另外,介绍了毛发中毒品分析的特点,通过分析毛发毒品的药理机制,总结出了一些高效、便利、快速的毒品分析方法,并对各种方法进行了介绍,得出了毛发中毒品分析结果的一些特点。     

Diagnosis of lethal poisoning with some substances used by toxicomaniacs

The authors analyze 62 expert conclusions on deaths from acute and chronic poisoning with various toxic substances used by toxicomaniacs. Forensic medical examination of corpses and forensic chemical analysis identified drugs, toluene, freon, organophosphorus compounds, and other toxins.     

法医毒理学的结果解释（上）

法医毒理学的主要任务是从生物检材中分析毒（药）物,并且推断毒（药）物浓度对死亡或行为能力的作用程度,结果解释是法医毒理学的最终目的。现代法医毒理学主要包括死后法医毒理学、滥用药物筛查和行为能力影响三个方面,由此探讨在进行结果解释时的诸多影响因素。进行法医毒理学的结果解释时应非常慎重,充分了解案情和调查结果,充分考虑毒（药）物的毒性、生物检材、药代动力学、体内再分布、药物交叉反应等多种因素,才能对案件作出较为准确的结果解释。     

Chemical Imaging of Human Fingermark by X-ray Photoelectron Spectroscopy (XPS)

X-ray photoelectron spectroscopy (XPS) is a widely used technique to characterize the surface chemistry of materials. It plays a crucial role in accessing qualitative and quantitative information and in detecting the presence of chemical functional groups on the surface of any material. The forensic methods available to detect and identify elements and organic/inorganic compounds are often destructive, so evidence cannot be re-analyzed. However, XPS allows rapid analysis of samples without damaging them. Recently, an increasing number of forensic researchers have begun to study certain chemical information on fingermarks. In this study, the authors aimed to present the applicability and power of XPS imaging in fingermark analysis which can also provide specific information about the fingermark chemical composition. Herein, monochromated X-ray (Al Kα) spot size was fixed at 50 μm. XPS mapping resulted in the acquisition of spectra at each pixel, in an array of 41 × 30 pixels with a step size of 50 μm. Then, a simple discussion has been made about how the scanned surface spectrum and basic snapshot spectra are used to identify different components at a fingertip of a scanned surface area (~3 mm²). Hence, a fingermark pattern contaminated with caffeine, TiO₂, and Pb/PbO deposited on the silicon wafer can be chemically mapped and visualized by XPS using principal component analysis (PCA). Thus, the present study showed the possible applicability of XPS for the identification of illicit drugs of abuse, gunshot residue, and skin care products on latent fingermark by mimicking a crime scene evidence.     

Evaluation of injuries features inflicted by shots from gas guns by emission spectral analysis

The authors describe a methodological approach to emission spectral analysis of material evidences aimed at evaluating the regularities of deposition of the shot metals at the site of injuries inflicted by gas guns. Injuries inflicted by gunshots with chemical cartridges and with shot cartridges, with and without obstructions, from different distances have been examined. The detected regularities may be useful in forensic medical expert evaluations by means of emission spectral analysis in cases with gas gunshots.     

The detection of beta-cypermethrin during forensic chemical expertise of biological materials

The optimal conditions for the isolation of beta-cypermethrin from biological materials by means of dioxane extraction have been developed. The possibility to purify beta-cypermethrin from endogenous impurities is demonstrated by combination of liquid-liquid extraction and chromatography through a silica gel column (L 40/100 mcm). It is shown that identification and quantitative determination of beta-cypermethrin extracted from the cadaveric liver tissues are possible using such techniques as thin-layer chromatography, electron spectrometry, and chromato-mass spectrometry. A method for forensic chemical expertise of the presence of beta-cypermethrin in biological materials is described.