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101.
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。 相似文献
102.
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。 相似文献
103.
目的 考查尿检材中海洛因的代谢物吗啡和单乙酰吗啡的液液萃取条件、三氟乙酰化和气相色谱电子捕获检测 (GC/ECD)条件。方法 以烯丙吗啡为内标 ,氯仿∶异丙醇 (9∶1)为液相萃取剂萃取尿中的吗啡和单乙酰吗啡 ,采用MBTFA衍生化 (三氟乙酰化 ) ,GC/ECD检测。结果 尿中加样相对回收率吗啡 89% ,单乙酰吗啡 75 % ,最小检测量吗啡 5 0ng ,单乙酰吗啡 10 0ng。通过实验兔的中毒实验 ,对尿检材进行了分析。 结论 所建立的萃取与检测方法分析海洛因中毒尿检材中的吗啡准确、灵敏 ,可用于海洛因的吸毒检验 相似文献
104.
Objective To establish a method for determination of two alcohol biomarkers (ethyl glucuronide, EtG;ethyl sulphate, EtS) in bloodstains via ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (UPLC-Q/eOrbitrap HRMS). Methods The bloodstains were prepared on clean glass slide where to have dropped the venous blood spiked of EtG or EtS, having them extracted with 50% hydrated methanol. The bloodstain-extracted supernatant was separated on a Synicronis C18 column (150mm×2.1mm×5.0μm) with gradient elution that was run through the mobile phases consisting of 0.1% formic acid (phase A) and acetonitrile: methanol (v/v 1:1) (containing 0.1% formic acid ) (phase B). MS tests were coupled with HPLC under HESI (heating electrospray ionization) source operated in negative ionization full-scan mode. Results Both EtG and EtS were linear with their calibration curves among the range of 0.2-100ng/patch (R2=0.9991, 0.9994), showing good recovery, intra-and inter-day precision less than 15%. The matrix effect was in the range of 85%-120%. Conclusion The method is effective to detect alcohol biomarkers (EtG and EtS) in bloodstains. © 2021, Editorial Office of Forensic Science and Technology. All rights reserved. 相似文献
105.
目的建立生物检材中同时检测百草枯(paraquat,PQ)及其主要代谢物单季铵盐(monoquat)、百草枯-单吡啶酮(paraquat-monopyridone,MP)、百草枯-联吡啶酮(paraquat-dipyridone,DP)、4-羧基-1-甲基吡啶盐(4-Carboxy-1-methylpyridinium ion,MINA)的液相色谱-串联质谱(LC-MS/MS)检测方法。方法以百草枯氘代内标(Paraquat-d8 Dichloride,PQ-D8)作为内标,检材样品调节pH后,经乙腈沉淀蛋白,使用不同色谱柱洗脱,在多反应监测模式下检测。结果百草枯PQ、monoquat、MP、DP、MINA的线性范围分别是5~800ng/mL、0.5~80ng/mL、5~800ng/mL、2.5~400ng/mL、2~320ng/mL(r均高于0.993),日内、日间精密度(RSDs)分别在5%~14%、3%~13%、3%~15%、5%~13%、2%~15%之间,准确度(RE)分别在91%~116%、80%~100%、80%~111%、85%~114%、91%~114%之间。生物样品处理后自动进样器上室温放置72h,各物质的准确度分别在90%~119%、56%~125%、60%~110%、78%~98%、83%~117%之间。结论本测定方法前处理过程简便,分离效果好,提取效率高,可使用本方法对疑似百草枯中毒的检材进行原体及代谢物的检测,为案件提供法律依据;本实验优化了课题组前期建立的生物样品中百草枯及monoquat、MP的检测方法,参考其案例结果,检测相应检材,对比分析,该检测方法在原体含量大幅下降时,痕量代谢物仍可检出。 相似文献
106.
A critical point of comparison between a fiber collected from a crime scene and a fiber from a known source is the color. Fiber dye analysis using thin-layer chromatography or ultraviolet (UV)-visible (Vis) microspectrophotometry provides useful, although limited, data for comparison. High-performance liquid chromatography-electrospray ionization mass spectrometry (LC/MS) overcomes these limitations by integrating chromatography, ultraviolet-visible spectroscopy, and mass spectrometry into a single instrument. In order to evaluate the applicability of the LC/MS to forensic fiber dye analysis, a multi-stage chromatographic method using acidified water and acidified acetonitrile was developed that separated and identified a mixture of 15 basic and 13 disperse dye standards. The LC/MS also detected and analyzed dyes extracted from individual 0.5 cm acrylic and polyester fibers, demonstrating its applicability to this type of analysis. With regard to the analysis of disperse dyes in polyester fibers, the replacement of pyridine with acetonitrile in the extraction system allowed direct injection of the extracts into the LC/MS. The advantage of the LC/MS over other instrumental methods of textile dye analysis is demonstrated by the analysis and differentiation of three black acrylic fibers: two fibers had similar UV-Vis spectra but were differentiated with chromatography and two had similar UV-Vis spectra and chromatograms but were differentiated using the mass spectrometer. 相似文献
107.
108.
目的建立肝中杀鼠酮的硅藻土提取方法和高效液相色谱检测法。方法取0.5g肝匀浆,加69/5HC10。沉淀蛋白,准确取1/2上清液倒入装有3.1g硅藻土的层析柱中,用10mL二氯甲烷或乙醚洗脱,洗脱液中加入安定作为内标,水浴浓缩,用0.2mL甲醇定容,供高效液相色谱分析。结果提取率分别为98.1%和99.9%,检出限分别为14ng/mL和13ng/mL。结论该方法简便、快速、提取率高,可作为法医毒物常规检测手段。 相似文献
109.
110.
Mercer JW Oldfield LS Hoffman KN Shakleya DM Bell SC 《Journal of forensic sciences》2007,52(2):383-388
This paper describes two analytical techniques used to separate and quantify gamma-hydroxybutyrate (GHB) and gamma-hydroxyvalerate (GHV). The first technique was a N,O-bis(trimethylsilyl)triflouro-acetimide-trimethylchlorosilane derivatization, followed by gas chromatography/mass spectrometry analysis using an HP-5 capillary column at a rate of 1.0 mL/min with a run time of 9.25 min. This technique was found to be sensitive (LOD 1 pg on column) and gave a low average error (5%) in a beverage study. When supplemented by a surrogate spike, the method yielded 97% analyte recovery from beverages. The second technique was high-performance liquid chromatography/UV (HPLC/UV) using a C-18 column with a (20:80% v/v) methanol:dibasic phosphoric buffer (10 mM, pH 3) at a rate of 1.00 mL/min with a run time of 7.5 min. UV detection occurred at 254 nm. This method was found to be less sensitive (LOD 0.05 microg on column) for direct analysis of aqueous samples. To remove interferences seen in the beverage study, a liquid-liquid extraction before HPLC analysis was tested. However, a decreased sensitivity (LOD 100 microg on column) and irreproducible peak profiles resulted. 相似文献