A novel method for cyanide quantification in human whole blood using ion chromatography with amperometric detection and its application to cyanide intoxication cases

Cyanide is a highly toxic agent that has been frequently used for suicide in South Korea. It is also used in various industrial fields, such as metal plating, in which many accidental cyanide intoxications have occurred. To overcome the disadvantages of conventional cyanide analysis methods, a simple and fast method for the analysis of cyanide in whole blood using ion chromatography (IC) with amperometric detection was developed in this study. Whole blood samples were deproteinized, diluted, and analyzed using an IC–amperometric detection system. The limits of detection and quantitation were 0.1 and 0.2 mg/L, respectively. The method showed good linearity in the range of 0.2 to 50 mg/L with R² > 0.99. The intra- and inter-assay precision and accuracy values were <10%. The established method was successfully applied to analyze whole blood samples from three cyanide intoxication cases.     

High performance liquid chromatographic determination of alcohols with reference to body distribution of methanol

A method has been developed on reverse phase high performance liquid chromatography for simultaneous determination of methyl, ethyl and isopropyl alcohols under refractive index detection using pure water as the mobile phase. A good separation has been achieved between these alcohols. Detector response was linear with a detection limit of 5 mg/100 ml. Recovery studies were performed by adding known amounts of methyl and ethyl alcohols to blood, lung and liver within the range 80–90%. The reproducibility of the results was always >90%. The quantitative distribution of methyl alcohol in postmortem body tissues and fluids has been reported in three cases of poisoning.     

Acidic and neutral drugs screen in blood with quantitation using microbore high-performance liquid chromatography–diode array detection and capillary gas chromatography–flame ionization detection

Blood previously acidified with aqueous saturated ammonium chloride solution was extracted with ethyl acetate. The dried extract was subjected to acetonitrile–hexane partition. The acetonitrile portion was analysed for the presence of acidic and neutral drugs by HPLC–DAD (200 mm×2.1 mm I.D. microbore ODS-Hypersil column) and GC–FID (25 m narrow-bore×0.25 mm I.D. HP-5 column with 0.33 μm film thickness). The protocol was found to be suitable for both clinical toxicology (including emergency toxicology) and postmortem toxicology. At least 66 drugs of interest were unequivocally identified by RRTs (HPLC) and UV spectra (DAD) match while another 12 were unequivocally identified by double RRTs match (HPLC and GC). Quantitation was facilitated by incorporating calibration blood standards in each assay batch. The five drugs most commonly encountered in clinical blood specimens (1150 cases) were: paracetamol (47.4% of the cases); chlormezanone (6.6%), theophylline (1.74%), naproxen (1.65%) and mefenamic acid (1.56%). The following drugs were detected in toxicologically significant quantities in postmortem blood specimens (245 cases): phenobarbitone (1.22% of the cases), naproxen (0.82%), chlormezanone (0.82%), theophylline (0.82%), carbamazepine (0.41%) and paracetamol (0.41%).     

高效薄层色谱法检测尿中硝西泮的代谢物7-氨基硝西泮

目的 建立用高效薄层色谱法定性及半定量测定人尿中硝西泮的代谢物7-氨基硝西泮(7ANIZ)含量的方法。方法 人口服治疗量10 mg硝西泮后,在pH 9条件下用乙醚进行提取,分析物斑点用氟罗里丝进行荧光显色,紫外灯下(366nm)观察荧光斑点;根据斑点荧光显色情况及强度进行7ANIZ定性及半定量检测。结果 尿中硝西泮代谢物7ANIZ检出限为5 ng/ml,测量限为15 ng/ml。结论 人口服治疗量10 mg硝西泮,用高效薄层色谱法可定性及半定量测定48 h内排泄尿中的7ANIZ。     

Proficiency testing (external quality assessment) of drug detection in oral fluid

Eighteen external quality assessment (proficiency testing) samples were prepared from client specimens collected with the Intercept^® oral fluid collection device and by spiking drug-free oral fluid. Samples were circulated in pairs at quarterly intervals to 13 UK and USA based laboratories for analysis by a panel of OraSure micro-plate Intercept^® enzyme immunoassay kits and hyphenated mass spectrophotometric techniques. During the survey, there was a single case of non-specificity in a false report for methadone. The major errors were of lack of sensitivity relative to the concentration thresholds specified for the immunoassays. The sensitivity for overall ‘present’/‘not found’ reports calculated as true positives/(true positives + false negatives) were for the amfetamine specific assay 50%, methyl-amfetamines 93%, barbiturates 64%, cannabinoids 73%, cocaine and metabolites 100%, benzodiazepines 69%, methadone 95%, opiates 79% (opiates excluding oxycodone 93%), phencyclidine 93% and human gamma-globulin 97%. A small number of the sensitivity errors were attributable to errors in chromatographic confirmation techniques.     

Analysis of Δ-tetrahydrocannabinol in oral fluid samples using solid-phase extraction and high-performance liquid chromatography–electrospray ionization mass spectrometry

An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography–mass spectrometry (LC–MS) has been developed and validated for the confirmation of Δ⁹-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm³, 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC + H⁺], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d₃-THC + H⁺]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r² = 0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette^®. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette^® collection, 26 of the 40 cases had an undetectable THC.     

中毒死者体内毒鼠强的GC/MS-SIM分析

一 1 9岁男子赌气吞服一白色粉末 ,1 0min后口鼻流血、抽搐 ,迅速送医院 ,经催吐、透析等方法治疗 5天后死亡。根据中毒症状和经验怀疑为毒鼠强中毒。用GC/NPD检验肝中毒鼠强有干扰。改用GC/MS -SIM法分析 ,心血、肝和胃组织中全部检出毒鼠强 ,浓度分别为 0 5 1 μg .mL- 1、0 4 5 μg .g- 1和 0 33μg .g- 1,和文献结果在同一水平。GC/MS -SIM对复杂检材中低含量毒鼠强测定具有更高的选择性 ,也具有较高的灵敏度 ,同时进一步证实毒鼠强排泄较慢 ,经过较长时间后在体内分布比较均匀     

HPLC测定复方丹皮酚凝胶中丹皮酚含量

目的:建立复方丹皮酚凝胶中丹皮酚的含量测定方法.方法:采用高效液相色谱法,色谱柱为SHIMADZU VP-ODS(4.6 mm×150 mm, μm),流动相为甲醇-水(50∶50),检测波长为274 nm.结果:丹皮酚进样量为0.05～0.30 μg时呈良好的线性关系(r =0.999 8).平均回收率为100%,SD为0.87%(n =5).结论:PLC法可用于复方丹皮酚凝胶的质量控制.     

The Effect of Temperature and Exposure Time on Stability of Cholesterol and Squalene in Latent Fingermarks Deposited on PVDF Membrane

Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation.     

Sample Mining and Data Mining: Combined Real-Time and Retrospective Approaches for the Identification of Emerging Novel Psychoactive Substances

Novel psychoactive substances (NPS) are synthetic drugs that pose serious public health and safety concerns. A multitude of NPS have been identified in the United States, often implicated in forensic investigations. The most common and effective manner for identifying NPS is by use of mass spectrometry and the true utility lies within nontargeted acquisition techniques. During this study, a liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) assay was developed, validated, and implemented for forensic toxicology testing. A SCIEX TripleTOF™ 5600 + with SWATH^® acquisition was used. Resulting data were compared against an extensive library database containing more than 800 compounds. The LC-QTOF-MS assay was applied to the reanalysis of biological sample extracts to discover emergent NPS. More than 3,000 sample extracts were analyzed, and more than 20 emerging NPS were detected for the first time. Among these were isopropyl-U-47700, 3,4-methylenedioxy-U-47700, fluorofuranylfentanyl, N-methyl norfentanyl, 2F-deschloroketamine, 3,4-methylenedioxy-alpha-PHP, eutylone, and N-ethyl hexedrone.