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81.
Bell SC Oldfield LS Shakleya DM Petersen JL Mercer JW 《Journal of forensic sciences》2006,51(4):808-811
This study examined microcrystals formed by silver with gamma-hydroxybutyric acid (GHB) and gamma-hydroxyvaleric acid (GHV), the five-carbon analog of GHB, in the presence of silver, copper, and lanthanide nitrates. Distinct microcrystals formed with silver (+1) and lanthanum (+3) ions but not with the copper (+2) ions. The crystals formed with GHB were distinctly different than those formed with GHV and in all cases, the drug microcrystals were easily distinguishable from reagent crystals. X-ray diffraction analysis provided definitive structure for the microcrystals. The morphological differences between the silver-GHB and silver-GHV crystals were characterized using simple measurements such as size and angles provided by image recognition software. The utility of the test for casework was demonstrated using spiked beverage samples. 相似文献
82.
目的建立生物检材中γ-羟基丁酸(GHB)的检测方法,研究GHB急性中毒大鼠体内GHB的分布,为GHB中毒的鉴定提供方法和评价依据。方法用GC/MS法检测生物检材中的GHB;以1000mg/kg剂量给大鼠灌胃使其染毒,分别于1h和3h处死,测定体液和组织中GHB的含量。结果测组织中内源性GHB的线性范围是1~20μg/g,R2=0.9974;测组织中外源性GHB的线性范围为100~1500μg/g,R2=0.9958。相对回收率为98%~103%。体内内源性GHB的含量均≤10μg/mL或10μg/g。尿液中GHB含量为最高,其他依次为:胃、血液、肠、肾、肺、脾、心、肝和脑。结论所建方法准确、便捷,适用于GHB中毒的鉴定;尿液是体内检测GHB的最佳检材。 相似文献
83.
化学显色法快速筛选饮料及尿液中γ-羟基丁酸和γ-丁内酯 总被引:1,自引:0,他引:1
目的建立化学显色法快速筛选饮料及尿液中γ-羟基丁酸(GHB)及其前体γ-丁内酯(GBL)的方法。方法在酸性条件下GHB转化为GBL,GBL和盐酸羟胺在碱性条件下生成γ-羟基丁酰羟胺,γ-羟基丁酰羟胺在酸性条件下和三氯化铁反应,生成紫红色的络合物。结果饮料中GHB最低检出浓度为0.5~2mg/mL,低于常见滥用质量浓度。该方法也可以用于尿液分析,最低检出质量浓度为0.5mg/mL。考察了常见有机溶剂和麻醉镇静药物的干扰。结论该方法简单、安全、快速,为临床和法庭科学实验室快速筛选GHB和GBL提供了便利。 相似文献
84.
85.
This is a systematic study that examines several acid prewashes and water rinses on paper bearing latent prints before its treatment with a silver physical developer. Specimens or items processed with this method are usually pretreated with an acid wash to neutralize calcium carbonate from the paper before the treatment with a physical developer. Two different acids at varying concentrations were tested on fingerprints. Many different types of paper were examined in order to determine which acid prewash was the most beneficial. Various wash times as well as the addition of a water rinse step before the development were also examined. A pH study was included that monitored the acidity of the solution during the wash step. Scanning electron microscopy was used to verify surface calcium levels for the paper samples throughout the experiment. Malic acid at a concentration of 2.5% proved to be an ideal acid for most papers, providing good fingerprint development with minimal background development. Water rinses were deemed unnecessary before physical development. 相似文献
86.
Objective
To compare the merit of four digestive methods (nitric acid plus hydrogen peroxide, proteinase K, nitric acid in Disorganization Can and Soluene-350) for extracting diatoms in order to choose the best digestive method for the diagnosis of drowning.Methods
Liver, kidney and bone marrow of rabbits were minced and then digested by four digestive methods separately with the following indices compared: (1) time demanded for complete digestion; (2) degree of digestion for different tissues; (3) the reclaiming ratio of diatoms; (4) the degree of digestive destruction to diatoms.Results
For sufficiently digesting the same tissue, the demanded times for the different methods ranked from the longest to the shortest were as follows: Soluene-350, proteinase K, nitric acid plus hydrogen peroxide, nitric acid in Disorganization Can. Nitric acid in Disorganization Can method and nitric acid plus hydrogen peroxide method digested the tissues more thoroughly than proteinase K, than Soluene-350 methods. For Cyclotella and Cybella, proteinase K method reclaimed most diatoms and nitric acid plus hydrogen peroxide method reclaimed less, while nitric acid in Disorganization Can and Soluene-350 methods reclaimed the least. For Navicula, the majority of diatoms could be extracted using proteinase K method, but only a few diatoms with other three methods. Under scanning electron microscopy (SEM), the structure of diatoms remained almost perfect after digestion with proteinase K, but destroyed to some extent with other three methods.Conclusion
This study demonstrated that different diatoms (in fresh or sea water) have different resistance to different digestive reagents. As far as the reliability and applicability of the diatom test is concerned, proteinase K method is of the best choice, nitric acid plus hydrogen peroxide can be its substitute. Soluene-350 cannot be used for extracting sea water diatoms. 相似文献87.
目的:优选金银花绿原酸煎煮提取的最佳工艺。方法:利用正交试验法,以总浸膏得率和绿原酸含量为指标,考察粉碎度、提取时间、提取次数和加水量对煎煮工艺的影响。结果:最佳工艺为金银花粉末过50目筛,加水量30倍,煎煮3次,每次煎煮30 m in。 相似文献
88.
目的:建立肠炎宁口服液中没食子酸含量测定方法.方法:采用高效液相色谱法(HPLC),色谱柱:Hypersil ODS C18(4.6 mm×150 mm);检测波长:271 nm;流动相:甲醇 0.5 g/L磷酸(5∶95);流速:1.0 ml/min.结果:没食子酸浓度为43.920~307.442 μg/ml时,与峰面积线性关系良好,平均回收率为100.2%,RSD为1.52%.结论:HPLC法准确、简便、快速,适合于该制剂的质量控制. 相似文献
89.
目的:测定瓜蒌皮中多糖含量,为瓜蒌皮的临床合理应用和质量评价提供科学依据.方法:以葡萄糖作为对照品,采用苯酚-硫酸比色法,在490 nm处测定多糖含量.结果:不同产地瓜蒌皮多糖含量差异不显著.结论:该测定方法操作简单,重复性好,结果准确可靠,可用于瓜蒌皮多糖的含量测定. 相似文献
90.
氟乙酰胺和氟乙酸的毛细管柱气相色谱检测 总被引:5,自引:0,他引:5
本文建立氟乙酰胺和氟乙酸的毛细管柱气相色谱检测方法,氟乙酰胺和氟乙酸的线性检测范围为0.0625mg/ml~4mg/ml和0.625mg/ml~20mg/ml,最小检出浓度为31.25ug/ml和625ng/ml.太原地区地摊所售鼠药87.5%含有氟乙酰胺,30%含有氟乙酸. 相似文献