Rapid isolation with Sep-Pak C18 cartridges and capillary gas chromatography of triazine herbicides in human body fluids.

A simple and rapid method, for the isolation of eight triazine herbicides from human serum and urine, using Sep-Pak C18 cartridges is presented. After mixing with distilled water, serum and urine samples containing the herbicides, were loaded on Sep-Pak C18 cartridges and eluted with either chloroform only or chloroform/methanol (9:1). The herbicides were detected by capillary gas chromatography with both flame ionization detection (FID) and nitrogen-phosphorus detection (NPD). Separation of eight triazine herbicides from each other and from impurities was generally satisfactory with the use of a non-polar DB-1 capillary column. Recovery of most compounds was excellent for both chloroform and chloroform/methanol (9:1) as elution solvents. Backgrounds were cleaner and evaporation time was shorter for the chloroform only than for the chloroform/methanol (9:1). The NPD gave sensitivity more than 10-20 times higher than that of FID.     

Tracking plant, fungal, and bacterial DNA in honey specimens

Consuming honey can result in adverse effects owing to poisoning by bacterial (botulism) or plant toxins. We have devised a method to extract polymerase chain reaction (PCR) amplifiable DNA of up to c. 400 bp in length based on dialysis of a 15-mL honey sample for 18 h against deionized water followed by sequential extraction using phenol, phenol/chloroform/isoamyl alcohol, chloroform/isoamyl alcohol, and ether. Sequence analysis of PCR products obtained using "universal" plant, fungal, and bacterial primers targeted to the ribosomal RNA genes has allowed us to identify six different orders of plants (Apiales, Fabales, Asterales, Solanales, Brassicales, and Sapindales), two orders of fungi (Entylomatales and Saccharomycetales), and six orders of bacteria (Sphingomonadales, Burkholderiales, Pseudomonadales, Enterobacteriales, Actinomycetales, and Bifidobacteriales) in a single honey specimen.     

利用16S rDNA序列鉴定常见嗜尸性蝇类种属

目的通过分析16S rDNA 551bp基因序列,鉴定常见嗜尸性蝇类种属。方法随机采集17个地区放置于室外草地的家兔尸体上7个种24只嗜尸性苍蝇样本,经形态学鉴定种类后,提取胸肌DNA,对16S rDNA 551bp基因片段进行PCR扩增,产物纯化、测序后上传GenBank;利用MEGA 4.0软件构建序列间的系统发育树,分析建立种内及种间进化分歧表。结果 24只样本16S rDNA序列分析显示7种蝇类可以较好聚类;其中棕尾别麻蝇种内进化分歧整体均数为2.8%,家蝇为1.5%,丽蝇科的5个种均在0.7%以内。上述7个蝇种的种间进化分歧均数在1.6%～7.1%之间。其中,棕尾别麻蝇、家蝇与其它蝇类的种间分歧均数在4.0%～7.1%之间。结论本文分析结果显示,蝇种间同源性相差明显,采用mtDNA 16S rDNA中551bp基因序列分析,可进行蝇种鉴定。     

Detection of malathion in a victim by gas chromatography/negative ion chemical ionization mass spectrometry

We experienced an autopsy case in which a 53-year-old woman committed suicide by ingesting allegedly a certain agricultural chemical. The blood and stomach contents, after extraction with acetonitrile and chloroform, were subjected to analysis by gas chromatography (GC)/negative ion chemical ionization (CI) mass spectrometry (MS). By total ion monitoring in the negative CI mode, a large peak appeared. The mass spectrum of the peak showed a strong anion at m/z 157, suggesting the presence of an organophosphorus pesticide. By measuring its spectrum in the positive electron impact (EI) mode, it was identified as malathion. The selected ion monitoring in the negative CI mode showed that the malathion peak was not interfered with by any impurities, and its background was very low. The sensitivity in the negative CI mode was about 5-10 times higher than that in the positive EI mode. Our data show that the GC/negative ion CI MS is useful for both screening and sensitive quantitation of organophosphorus pesticides.     

吸入二氯甲烷和氯仿中毒后溺水死亡案例的法医毒物学分析

国外曾有一些二氯甲烷在工业事故中引起死亡及氯仿用于自杀、谋杀和作为成痛剂吸食而致死的案例检验报道[1-6]，国内尚未见报道。本文采用顶空气相色谱分析方法测定了二氯甲烷和氯仿在3名死亡人员及1只死鱼鹰体内的分布情况，并习国外有关文献资料进行了比较讨论，确定了3人因吸入二氯甲烷和氯仿而引起中毒昏迷，但昏迷后落水溺死是其最终致死原因。案情摘要1991年1月22日上午，某乡数只捕鱼小船，途经某化工总厂正在排放废水、废气的排放口时，船上渔民及数只渔鹰接连落水，致使3人和6只渔鹰死亡。1人经抢救脱脸，据脱险者讲：他与其他3人…     

Analysis of psilocybin and psilocin in Psilocybe subcubensis Guzmán by ion mobility spectrometry and gas chromatography-mass spectrometry

A new method has been developed for the rapid analysis of psilocybin and/or psilocin in fungus material using ion mobility spectrometry. Quantitative analysis was performed by gas chromatography-mass spectrometry after a simple one-step extraction involving homogenization of the dried fruit bodies of fungi in chloroform and derivatization with MSTFA. The proposed methods resulted in rapid procedures useful in analyzing psychotropic fungi for psilocybin and psilocin.     

Efficiency evaluation of a DNA extraction and purification protocol on archival formalin-fixed and paraffin-embedded tissue

Formalin-fixed and paraffin-embedded tissue (FF-PET) is an invaluable resource for retrospective molecular genetic studies, but the extraction of high-quality genomic DNA from FF-PET is still a problematic issue. Despite the range of DNA extraction methods currently in use, the association of phenol–chloroform extraction and silica-based purification protocols, reported in ancient DNA studies on archaeological bones, has, to our knowledge, not been used for DNA extraction from FF-PET yet. The present study compared the efficiency of three DNA extraction and purification protocols from two different FF-PET substrates, heart and liver, by using quantitative PCR and multiplex amplification.We showed that the method, using phenol–chloroform and the QIAamp DNA mini^® Kit (Qiagen), was the most effective DNA extraction and purification method and that the DNA quantity extracted from liver is statistically more important than that extracted from heart. Autosomal STR typing by multiplex amplifications gave partial allelic profiles with only small size products (less than 300 bases) amplified, suggesting that DNA extracted from FF-PET was degraded.In conclusion, the protocol presented here, previously described in studies on ancient bones, should find application in different molecular studies involving FF-PET material.     

The indirect detection of bleach (sodium hypochlorite) in beverages as evidence of product tampering

Bleach (sodium hypochlorite) has been identified as the adulterant in a relatively large number of product tamperings that have been investigated by the Forensic Chemistry Center (FCC) of the U.S. Food and Drug Administration. In this work, household bleach was added to 23 different beverages at each of three levels. The impact of sodium hypochlorite on these beverages over a 13-day study period was evaluated using the following techniques: diphenylamine spot test for oxidizing agents, potassium iodide-starch test paper for oxidizing agents, pH, iodometric titration for quantitating hypochlorite, ion chromatography for chloride and chlorate quantitation, automated headspace sampling with gas chromatography-flame ionization detection (GC-FID) for determination of chloroform, and visual and organoleptic observations. This study has shown that hypochlorite is fragile when added to most common beverages and typically breaks down either partially or completely over time. In cases where a beverage is suspected of being adulterated with bleach but tests for hypochlorite are negative, it is still possible to characterize the product to demonstrate that the results are consistent with the addition of bleach. An adulterated product will give a positive test for oxidizing agents using the diphenylamine spot test. It is likely that the pH of the adulterated product will be higher than a control of that product. Ion chromatographic analysis shows elevated chloride and chlorate as compared with a control. And, chloroform may also be detected by GC-FID especially if the beverage that was adulterated contains citric acid.     

Identification of the source of ivory idol by DNA analysis

In this study, we describe a forensic case dealing with the identification of the source of the processed ivory object by DNA analysis. Two pieces of Lord Krishna's idols from a shop were confiscated by an investigating agency of the Indian government and forwarded to us to identify the source of its origin. We succeeded in isolating DNA from both processed ivory idols by using the phenol/chloroform DNA extraction method. The extracted DNA was subjected to PCR amplification using an elephant-specific mitochondrial DNA (mtDNA) D-loop marker. DNA sequence analysis of the amplified fragment of mtDNA D-loop region confirmed that the idols were consistent with Asian elephant with 99% similarity.     

二氯甲烷和氯仿中毒的顶空气相色谱分析法

应用顶空气相色谱分析方法检测生物样品中的二氯甲烷(CH_2Cl_2)和氯仿(CHCl_2),并考察了20余种实验室中常见有机溶剂的干扰情况,测定了血中二氯甲烷和氯仿的线性范围及检出限,其方法回收率超过80％,方法测定变异系数小于16％,其中体液测定变异系数小于5％。该分析方法已成功地用于案件的鉴定工作。     

尿液中丁丙诺啡的提取方法

目的建立尿液中丁丙诺啡提取方法。方法尿液加pH 7.0缓冲液后,用三氯甲烷进行液相萃取或加pH 10.8缓冲液后,用401有机担体作吸附剂、三氯甲烷作洗脱剂进行固相萃取,GC/NPD法检测。结果尿液中丁丙诺啡液相萃取萃取率可达86.6%以上,固相萃取可达83.0%以上。结论两种提取方法萃取率高,可用于尿液中丁丙诺啡的提取。     

Unconjugated morphine in blood by radioimmunoassay and gas chromatography/mass spectrometry

Morphine, the active metabolite of heroin, is rapidly inactivated by glucuronidation at the 3 carbon. Unconjugated (pharmacologically active) morphine was measured in postmortem blood by radioimmunoassay using an antibody-coated tube kit. The kit shows less than 0.2% cross-reactivity with codeine and morphine-glucuronide. Unconjugated morphine concentrations were confirmed by gas chromatography/mass spectrometry (GC/MS) using deuterated morphine as the internal standard. The blood was precipitated with 10% trichloroacetic acid (TCA) and concentrated hydrochloric acid (HCl), centrifuged, and decanted. The supernatant was then either diluted (unhydrolyzed) or heated to 100 degrees C, 30 min (hydrolyzed), followed by a wash with 4:1 chloroform:isopropranol. The upper aqueous layer was then saturated with sodium bicarbonate (NaHCO3) and extracted with 4:1 chloroform:isopropranol. The organic layer was evaporated, derivatized with trifluoroacetic anhydride (TFA), and analyzed by selected ion monitoring (SIM) GC/MS. Comparison of the results for unconjugated morphine by radioimmunoassay and unhydrolyzed morphine by GC/MS gave a correlation coefficient of r = 0.98, n = 100. Unconjugated morphine ranged from 0 to 100% of total morphine with a mean of 42%, n = 200, for heroin or morphine involved deaths. Review of 56 putative rapid deaths gave a mean of 68% unconjugated morphine with a range of 26 to 100%. The ratio of unconjugated to total morphine was found to be stable in postmortem blood after more than a year of storage at room temperature, within the precision of the method.     

Solid phase extraction method for rapid isolation and clean-up of some synthetic pyrethroid insecticides from human urine and plasma.

A simple and rapid method for the isolation of seven synthetic pyrethroid insecticides (methothrin, fenpropathrin, cyhalothrin, permethrin, cypermethrin, fenvalerate, deltamethrin) with a solid phase extraction (SPE), utilizing Sep-Pak C18 cartridges, from human urine and plasma is presented. The detection of the insecticides was performed using a wide bore capillary gas chromatograph (GC) with flame ionization detection (FID). The insecticide-containing samples mixed with 70% methanol were directly applied to the cartridges and eluted with 2 ml chloroform. The recoveries using the cartridges were between 90-102% for urine and 81-93% for plasma. Mixing samples with 70% methanol prior to extraction, seems very useful for the screening of synthetic pyrethroid insecticides.     

A Concentrated Hydrochloric Acid-based Method for Complete Recovery of DNA from Bone

The successful extraction of DNA from historical or ancient animal bone is important for the analysis of discriminating genetic markers. Methods used currently rely on the digestion of bone with EDTA and proteinase K, followed by purification with phenol/chloroform and silica bed binding. We have developed a simple concentrated hydrochloric acid-based method that precludes the use of phenol/chloroform purification and can lead to a several-fold increase in DNA yield when compared to other commonly used methods. Concentrated hydrochloric acid was shown to dissolve most of the undigested bone and allowed the efficient recovery of DNA fragments <100 bases in length. This method should prove useful for the recovery of DNAs from highly degraded animal bone, such as that found in historical or ancient samples.     

Radiographic demonstration of esophageal and tracheal fistulas at autopsy using a contrasting medium that vulcanizes at room temperature

Esophageal and tracheal fistulas, which occur in 0.05% of medicolegal autopsies, were demonstrated in three cases by a postmortem radiographic technique using silicone rubber/lead oxide as a contrasting medium that vulcanizes at room temperature. In one 83-year-old male, a tracheoesophageal fistula was detected, which had developed after surgical repair of an esophageal rupture caused by a flexible fiberoptic endoscope. In a second case, carcinoma of the esophagus in a 78-year-old male had eroded the trachea and arcus of the aorta creating a fatal tracheoesophagoaortic fistula. In a third case, 55-year-old female developed a tracheobrachicephalic artery fistula as a result of an infiltrating cystic adenocarcinoma of the trachea, resulting in a fatal hemorrhage into the trachea. The results of this study indicate that diagnostic radiologic methods using a vulcanized contrasting medium are useful in supplementing normal dissection in autopsy cases with suspected fistulas of the esophagus or trachea.     

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F(254) plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm x 150 mm, 5 microm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.     

Analyzing Salvia Divinorum and its Active Ingredient Salvinorin A Utilizing Thin Layer Chromatography and Gas Chromatography/Mass Spectrometry

Abstract:  In recent years, Salvia divinorum has become a major focus by state legislatures throughout the United States looking to prohibit the sale of the psychoactive plant. After researching testing procedures presented in the literature and those employed by crime laboratories throughout the country, it was decided that thin layer chromatography (TLC) and gas chromatography/mass spectrometry (GC/MS) were the methods to use to analyze plant material for salvinorin A. With TLC, salvinorin A was detected from extracted plant material and was easily distinguishable from 13 other Salvia species as well as Cannabis sativa L. (marijuana). When using GC/MS, salvinorin A was best extracted from plant material with chloroform at ambient temperature when using a nonpolar solvent and acetone at ambient temperature when using a polar solvent. By utilizing these techniques, criminalists are now able to confirm the presence of salvinorin A in a submitted plant material suspected to be Salvia divinorum .     

Multiple homicides as a result of chloroform poisoning: case report and experimental study.

Two cases (involving five murder victims) of multiple homicide by inhalational chloroform intoxication are reported. In the discussion of the findings the valence of toxicological analyses is underlined with regard to the possibility of forcible external suffocation due to occlusion of the respiratory orifices by means of a chloroform-soaked soft covering. In addition storage experiments were performed at +4, +20 and -20 degrees C with cadaver blood mixed with chloroform. The optimal solution for avoiding volatile losses was stored in glass tubes with ground glass stoppers. In cases of unclear death in which involvement of volatile substances is suspected it is, therefore, advisable to preserve an additional blood sample at -20 degrees C in glass tubes that are only opened for the analysis of volatile substances.     

The differential elution of drugs from XAD-2 resin.

Biological fluids and tissue extracts prepared according to a previously published method were passed through a column of Amberlite XAD-2 resin for removal of drugs. The differential elution of the adsorbed drugs from the resin was performed by sequential elution of the drugs in four steps. The column was first washed with 30 ml of 0.05M sodium acetate buffer, pH 4.55. Drugs exhibiting acidic or neutral characteristics were then eluted from the column with 100 ml of chloroform in 20-ml aliquots. The column was then washed with 30 ml of 0.1M potassium carbonate, which was discarded. Drugs exhibiting basic characteristics were then eluted from the column with 100 ml of chloroform:isopropanol (3:1) in 20-ml aliquots. Sensitivity of drug detection with this method by thin-layer chromatography was 0.5 mug/ml in a 10-ml sample for nearly all drugs tested.     

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography–mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F₂₅₄ plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm×150 mm, 5 μm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.