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作者用分离纯化的GC蛋白免疫新西兰兔制备了抗GC血清。鉴定结果表明,抗GC血清与进口商品抗GC血清特异性相同;与人血清其他蛋白没有交叉反应。琼脂双向扩散法测得抗血清效价为128;可检出GC蛋白的最低浓度为3.1μg/ml。免疫电泳法可测出入血清三种GC表型。 相似文献
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毛发中甲基苯丙胺及代谢产物苯丙胺的分析研究 总被引:5,自引:2,他引:3
介绍了毛发中甲基苯丙胺( MAMP)及代谢产物苯丙胺( AMP)的 GC/NPD、 GC/MS的定性定量分析方法。毛发用 0.1 mol/L HCl水解, 4-苯基丁胺( 4- PBA)为内标,液-液提取,三氟乙酸酐( TFA)衍生化。毛发用量为 10mg,检出限为 GC/NPD 0.5ng/mg, GC/MS 0.1ng/mg,回收率大于 78%。该方法成功应用于染毒豚鼠毛发中 MAMP及其代谢产物 AMP浓度变化过程的测定。 相似文献
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Carlos A. Valdez PhD Alexander K. Vu BSc Saphon Hok PhD Armando Alcaraz 《Journal of forensic sciences》2023,68(6):1923-1931
The benzylation of three low molecular weight N,N-disubstituted ethanolamines related to chemical warfare agents (CWAs) to furnish derivatives with improved gas chromatography-mass spectrometry (GC-MS) profiles is described. Due to their low molecular weight and polar nature, N,N-disubstituted ethanolamines are notoriously difficult to detect by routine GC-MS analyses during Organisation for the Prohibition of Chemical Weapons (OPCW) proficiency tests (PTs), particularly in scenarios when they are present at low levels (~1–10 ppm) amidst more abundant interferences. Our studies revealed that the optimal derivatization conditions involved the treatment of the ethanolamine with benzyl bromide in the presence of an inorganic base (e.g., Na2CO3) in dichloromethane at 55°C for 2 h. This optimized set of conditions was then successfully applied to the derivatization of N,N-dimethylethanolamine, N,N-diethylethanolamine and N,N-diisopropylethanolamine present separately at 1 and 10 μg/mL concentrations in a glycerol-rich matrix sample featured in the 48th OPCW PT. The benzylated derivatives of the three ethanolamines possessed retention times long enough to clear the massive glycerol-containing matrix interferences. The protocol herein is introduced as an alternative method for derivatization of these CWA and pharmaceutically important species and should find broad applicability in laboratories where routine forensic analysis is carried out. 相似文献
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目的建立甲氰菊酯家兔灌胃染毒致死模型和生物检材中甲氰菊酯的气相色谱和气相色谱-质谱联用检测方法,研究甲氰菊酯在家兔体内的死后分布规律。方法家兔6只,甲氰菊酯经口灌胃染毒,死亡后迅速解剖,取心血、外周血、肝等组织,气相色谱和气相色谱-质谱联用法检测甲氰菊酯含量;部分组织经甲醛固定,HE染色,光镜观察其病理改变。结果家兔染毒后2~3h出现中毒表现,染毒后4.5~8h死亡。气相色谱和气相色谱-质谱联用法均检测到甲氰菊酯。甲氰菊酯在家兔体内死后分布为胃壁(458.92±32.82)μg/g、肾(46.47±6.30)μg/g、肝(35.79±20.11)μg/g、大脑(28.77±10.52)μg/g、心(26.49±4.10)μg/g、脾(22.23±5.37)μg/g、胆汁(10.87±1.42)μg/mL、肺(10.32±0.78)μg/g、周围血(8.14±1.12)μg/mL和心血(8.20±1.83)μg/mL。结论甲氰菊酯的灌胃染毒致死模型、气相色谱和气相色谱-质谱联用检测方法及死后分布规律可应用于甲氰菊酯中毒死亡案件的法医学鉴定及法医毒物动力学研究。 相似文献
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Zaitsu K Katagi M Kamata T Kamata H Shima N Tsuchihashi H Hayashi T Kuroki H Matoba R 《Forensic science international》2008,177(1):77-84
A newly synthesized designer drug, para-methoxyethylamphetamine (PMEA) was unexpectedly detected in the postmortem specimens of fatality involving drug intoxication in 2005, Japan. For unequivocal identification, the isomeric discrimination of PMEA and its positional-isomers was performed by GC/MS with the trifluoroacetylation. In order to prove the intake of PMEA, the characteristic metabolites of PMEA were also identified by GC/MS analysis of the urine specimen with trifluoroacetylation. As a result, para-methoxyamphetamine, para-hydroxyethylamphetamine (POHEA) and para-hydroxyamphetamine were identified as the major metabolites of PMEA. For the quantitative analyses of PMEA and its three metabolites in body fluids, an automated column-switching LC/MS procedure was developed, and applied to the postmortem blood and urine specimens. In this fatal case, blood concentration of PMEA was estimated to be 12.2 microg/mL and this level seemed extremely high in comparison with lethal blood-levels of its analogues, representing acute-intoxication of the victim. Based on the quantitative results, PMEA was found to be extensively metabolized to POHEA via O-demethylation, partly followed by its conjugation. 相似文献