Use of a solid absorbent and an accelerant detection canine for the detection of ignitable liquids burned in a structure fire

ABSTRACT: Ignitable Liquid Absorbent^™ (ILA), a commercial solid absorbent intended to assist fire scene investigators in sample location and collection, has been field tested in three separate room fires. The ability of the ILA to detect and absorb different amounts of gasoline, odorless paint thinner, and camp fuel on two different substrates after a full-scale burn was assessed against results from an accelerant detection canine and laboratory analysis using gas chromatography-mass spectrometry (GC-MS). The canine correctly alerted on most of the panels that contained an ignitable liquid after the fire, while the ILA indicator dye failed to indicate in the presence of gasoline and camp fuel. GC-MS results for ignitable liquid residue from each panel and from the ILA showed that ILA absorbed odorless paint thinner and camp fuel from most of the test panels, but failed to absorb gasoline from the panels on which gasoline was confirmed to be present.     

Quantitative Analysis of Gamma‐Hydroxybutyrate at Endogenous Concentrations in Hair using Liquid Chromatography Tandem Mass Spectrometry

Abstract: A method capable of quantifying endogenous concentrations of gamma‐hydroxybutyrate (GHB) in human head hair was developed and validated using liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS). Hair was digested under alkaline conditions, and GHB was isolated using liquid–liquid extraction. LC/MS/MS was performed using atmospheric pressure chemical ionization in the negative mode, multiple reaction monitoring, and deuterated internal standard (GHB‐D₆). Linearity was observed between 0.1 and 100 ng/mg GHB (R² = 1.000). The limits of detection and quantitation in human hair were 0.2 and 0.4 ng/mg, respectively. Accuracy at 2 ng/mg and 10 ng/mg was determined to be 97% and 94%, and intra‐assay CVs at these concentrations were 5.2% and 7.4% (n = 4). Beta‐hydroxybutyrate (BHB), alpha‐hydroxybutyrate, gamma‐butyrolactone, and 1,4‐butanediol did not produce an interference, and there was negligible ion suppression or enhancement from the matrix.     

LC/MS分析血浆中丁丙诺啡

目的建立血浆中丁丙诺啡液相色谱/质谱（LC/MS）分析方法。方法在含有丁丙诺啡的血浆中,加入内标奋乃静,加pH10.8缓冲溶液,用401有机担体作吸附剂、三氯甲烷作洗脱剂固相萃取,N2挥干,用50μL流动相定容后进行LC/MS分析。色谱条件：Thermo Hypersil-HyPURITY C18（150×2.1mm,5μm）,柱温：40℃,流动相：10mmol/LNH4AC（pH3.4）∶甲醇∶乙腈=36∶52∶12,流速：0.22mL/min。结果方法的线性范围为0.05～5.0μg/L（r=0.9998）,定量限0.05μg/L,检出限0.01μg/L（S/N=3）;3个浓度的质量控制样品（0.1μg/L,0.5μg/L,2.0μg/L）平均回收率分别为86.40%,92.72%,92.57%,RSD分别为4.51%,3.34%,2.09%。结论该方法操作简便、灵敏度高,可用于涉毒案件血浆中丁丙诺啡的分析。     

Simultaneous Determination of 13 Anticoagulant Rodenticidesin Human Blood by Liquid Chromatography–Tandem Mass Spectrometry and its Application in Three Poisoning Cases

Anticoagulant rodenticides are widely used for rodent control around the world. A rapid and sensitive method was developed and validated for the simultaneous determination of 13 anticoagulant rodenticides (coumafuryl, pindone, valone, warfarin, coumatetralyl, coumachlor, diphacinone, dicumarol, chlorophacinone, bromadiolone, difenacoum, flocoumafen, and brodifacoum) in human blood by liquid chromatography–tandem mass spectrometry. After liquid–liquid extraction, the anticoagulant rodenticides were separated on an Eclipse Plus C18 column. Linearities were observed for each analyte in blood ranging from 0.5 to 50 ng/mL, with correlation coefficients over 0.99. The limits of detection ranged from 0.01 to 0.2 ng/mL, and the limits of quantification were 0.5 ng/mL for all analytes. The intraday and interday precisions were <15%, and accuracies ranged from 80.3% to 111.0%. This validated method with high sensitivity has been applied in three anticoagulant rodenticide poisoning cases and has been used successfully in monitoring blood concentrations for months.     

5F-UR-144的热不稳定性研究

目的利用气相色谱-质谱法(GC-MS)、液相色谱-四级杆-飞行时间质谱(LC-Q-TOF/MS)和核磁共振光谱法(NMR)研究合成大麻素5F-UR-144遇热分解的具体变化情况。方法对照品用无水乙醇定容稀释后,经GC-MS和LC-Q-TOF/MS检测得到对应的色谱图和质谱图;对照品分别于常温和280℃密封加热后用无水乙醇定容稀释,经LC-Q-TOF/MS和NMR检测得到对应的质谱图、¹H和¹³C核磁共振波谱;对照品分别于常温逐步提升至300℃密封加热后用无水乙醇定容稀释,经LC-Q-TOF/MS检测得到对应的色谱图。结果5F-UR-144在高温下会开环产生新的物质;5F-UR-144从130℃开始分解,随着温度升高分解程度提升,240℃时分解率达到98%;随着温度继续升高,超过260℃,分解产物会碳化。结论基于5F-UR-144的热不稳定性,在检测时应考虑若通过烫食方式吸食5F-UR-144,其进入人体的成分会发生变化;气相色谱或气相色谱-质谱法不适合定量检测5F-UR-144。     

液相色谱-串联质谱法测定血液和尿液中秋水仙碱

目的建立检测血液和尿液中秋水仙碱的液相色谱-串联质谱法。方法0.5mL血液或尿液以丁丙诺啡为内标,经pH9.2硼酸盐缓冲溶液碱化后,用乙酸乙酯进行提取,在ZORBAX SB-C18液相柱(150mm×2.1mm×5μm)上以V(甲醇)∶V(20mmol/L乙酸铵和0.1%甲酸缓冲溶液)=80∶20为流动相,流速为0.2mL/min,采用电喷雾正离子模式离子化、多反应监测模式检测秋水仙碱,内标法定量。结果血液、尿液中秋水仙碱与内标丁丙诺啡色谱分离良好,秋水仙碱在0.1~50 ng/mL内均具有良好的线性,相关系数>0.9990,最低检出限为0.05ng/mL,方法回收率为94%~116%,日内与日间精密度(RSD)均小于8.5%。结论所建LC-MS-MS方法灵敏度高、操作简便、快速、准确,适用于血液及尿液等生物检材中痕量秋水仙碱成分的检测。     

鸡猪排泄物中恩诺沙星和环丙沙星含量HPLC检测方法的建立

建立了测定鸡、猪排泄物中恩诺沙星及环丙沙星含量的高效液相-荧光检测方法。将猪粪和鸡粪尿混合物样品分别用甲醇氨水溶液和醋酸甲醇溶液浸提,猪尿用固相萃取小柱富集净化,流动相为乙腈-三乙胺磷酸溶液(0.02 mol/L),荧光激发波长280 nm,发射波长450 nm。检测结果表明,排泄物样品中恩诺沙星和环丙沙星含量的检测定量限,鸡粪尿混合物为0.010μg/g,猪尿0.005μg/mL,猪粪为0.020μg/g。外标法标准曲线的线性范围鸡粪尿混合物中恩诺沙星为0.010~100.000μg/g、环丙沙星为0.010~50.000μg/g,猪尿和猪粪中恩诺沙星和环丙沙星的线性范围分别为0.005~0.500μg/mL和0.020~1.000μg/g。恩诺沙星和环丙沙星的回收率分别大于75%和88%。HPLC方法的样品前处理和检测方法简便、快捷,准确性较微生物检测法高。     

HPLC-UVD/FLD法测定血中氟乙酸类杀鼠剂

目的采用水相催化衍生化-液相色谱-紫外/荧光检测分析法,检测血中氟乙酸类杀鼠剂。方法血样经乙腈沉淀蛋白后,加入衍生化试剂4-溴甲基-7-甲氧基香豆素、催化剂四丁基溴化铵,在80℃水浴中衍生化反应120min,衍生产采用液相色谱-紫外/荧光检测分析。结果紫外检测法:氟乙酸根浓度在0.38～38.50μg/mL之间线性关系良好,最低检出限为0.10μg/mL;荧光检测法:氟乙酸根浓度在0.15～15.40μg/mL之间线性关系良好,最低检出限为0.050μg/mL。结论水相催化衍生化-液相色谱-紫外/荧光检测分析方法具有较好的灵敏度、准确性和精密度,可用于实际案例检测。     

HPLC-DAD双波长法同时测定脑络欣通胶囊中阿魏酸及天麻素含量

目的 建立双波长同时测定脑络欣通胶囊中天麻素和阿魏酸含量的方法,为脑络欣通的质量控制提供依据。 方法 采用高效液相色谱-二极管阵列检测器和Welch Materials C8色谱柱（250 mm×4.6 mm,5 μm）。流动相：乙腈-0.01%磷酸;梯度洗脱（乙腈：0～10 min,6%;10～30 min,6%→35%）;流速：1.0 mL/min;柱温：35 ℃;检测波长：320 nm（阿魏酸）和222 nm（天麻素）。结果 在30 min内,实现了阿魏酸与天麻素双波长同时测定,二者含量分别在0.20～2.39 μg（r＝0.999 9）和0.20～2.41 μg（r＝0.999 8）范围内与峰面积呈现良好的线性关系,平均加样回收率分别为99.5%和99.1%（n＝6）。 结论 双波长检测对复方中阿魏酸与天麻素定量更准确,二者同时测定能有效提高分析效率,该方法可用于脑络欣通胶囊的质量控制。     

不同产地牵牛子生品及炒制品咖啡酸含量测定

目的 通过测定不同产地牵牛子生品及炒制品中咖啡酸含量,探讨产地和炮制方法对牵牛子质量的影响。方法 采用高效液相色谱法测定牵牛子生品及炒制品中咖啡酸的含量。色谱柱：Shim-pack ODS（4.6 mm×150 mm,5 μm）;柱温：30 ℃;流动相：乙腈-0.04%磷酸水溶液,梯度洗脱;检测波长为325 nm。结果 河南产牵牛子咖啡酸含量最高,山西产牵牛子咖啡酸含量最低,其他产地牵牛子咖啡酸含量居中,牵牛子炒制品较生品中咖啡酸含量均有不同程度的降低。结论 不同产地牵牛子咖啡酸含量不同,炮制后,咖啡酸含量降低,咖啡酸可作为牵牛子的评价指标之一。