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151.
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
152.
Abstract: Illicit distribution of various illicit or counterfeit drugs containing sildenafil and tadalafil has increased and caused noticeable problems in Korea. This study has been performed to determine the content range of sildenafil and tadalafil in various fake drugs. Among the illicit or counterfeit drugs seized by Korean authorities, 105 exhibits were used for the quantification. HPLC–UV analysis of methanol extractions was used for separation and quantitation of the two target compounds. The most abundant type of fake drug was counterfeit Viagra® tablets. Sildenafil was found in 73 exhibits, and tadalafil was found in seven exhibits. Twenty‐five exhibits out of the 105 contained both sildenafil and tadalafil. The contents of sildenafil ranged from 4.3 to 453.2 mg; for tadalafil, the range was 2.2–40.4 mg. The proportion of cases of having more than 100 mg of sildenafil was 50% and 78% had more than 20 mg of tadalafil. 相似文献
153.
目的:建立乐脉软胶囊中芍药苷的含量测定方法.方法:采用高效液相色谱法测定该药中芍药苷的含量,色谱条件:汉邦Lichrospher C 18 柱(250.0 mm×4.6 mm,5 μm),乙腈水冰醋酸(16∶84∶0.8)为流动相,检测波长230 nm,柱温25℃,流速0.8 ml/min.结果:芍药苷浓度为 7.75~ 124.00 μg/ml时峰面积与浓度线性关系良好, r =0.999 7,平均回收率为97.50%,RSD为 1.62%.结论:HPLC简便易行,准确可靠,专属性强,可用于乐脉软胶囊的质量控制. 相似文献
154.
变性高效液相色谱及其在法医DNA分析中的应用 总被引:2,自引:1,他引:1
变性高效液相色谱(DHPLC)是目前检测基因突变的最佳技术平台之一。本文简要介绍了DHPLC的工作原理及主要技术特点,并对其在法医DNA分析中的应用进行综述。 相似文献
155.
Erwin Vermeij M.S. Peter Zoon Ph.D. Mayonne van Wijk M.S. Reza Gerretsen M.D. 《Journal of forensic sciences》2015,60(3):770-776
Dissolving bodies is a current method of disposing of human remains and has been practiced throughout the years. During the last decade in the Netherlands, two cases have emerged in which human remains were treated with acid. In the first case, the remains of a cremated body were treated with hydrofluoric acid. In the second case, two complete bodies were dissolved in a mixture of hydrochloric and sulfuric acid. In both cases, a great variety of evidence was collected at the scene of crime, part of which was embedded in resin, polished, and investigated using SEM/EDX. Apart from macroscopic findings like residual bone and artificial teeth, in both cases, distinct microscopic residues of bone were found as follows: (partly) digested bone, thin‐walled structures, and recrystallized calcium phosphate. Although some may believe it is possible to dissolve a body in acid completely, at least some of these microscopic residues will always be found. 相似文献
156.
Loong Chuen Lee Ab Aziz Ishak Ameeta A/P Nai Eyan Anas Fahmi Zakaria Nurul
Syahiera Kharudin Nor Azman Mohd Noor 《法庭科学研究(英文)》2022,7(4):761
Soil is of particular interest to the forensic community because it can be used as valuable associative evidence to link a suspect to a victim or a crime scene. Liquid chromatography is a powerful analytical tool for organic compound analysis. Recently, high-performance liquid chromatography (HPLC) has proven to be an efficient method for forensic soil analysis, especially in discriminating soils from proximity locations. However, ultra-performance liquid chromatography (UPLC), which is much more sensitive than HPLC, has never been explored in this context. This study proposed a UPLC method for profiling non-volatile organic compounds in three Malaysian soils (red, brown and yellowish-brown soils). The three soils were analysed separately to assess the effects of individual chromatographic parameters: (a) elution programme (isocratic vs. two gradient programmes); (b) flow rate (0.1 vs. 0.2 mL/min); (c) extraction solvent (acetonitrile vs. methanol) and (d) detection wavelength (230 vs. 254 nm). The injection volume and total run time were set to 5 µL and 35 min, respectively. Consequently, each soil sample gave 24 different chromatograms. Results showed that the most desirable chromatographic parameters were (a) isocratic elution; (b) flow rate at 0.2 mL/min and (c) acetonitrile extraction solvent. The proposed UPLC system is expected to be a feasible method for profiling non-volatile organic compounds in soil, and is more chemical-efficient than a comparable HPLC system. 相似文献
157.
目的建立葡萄叶中2甲4氯、2,4-滴和2,4-滴丙酸3种苯氧羧酸类除草剂的二氯丙基酯化-电子俘获检测气相色谱分析法。方法样品捣碎、添加内标2,4-二氯苯乙酸、酸化、用乙醚提取,提取液用液液分配法净化,净化后挥干有机溶液,用硫酸和1,3-二氯丙-2-醇进行酯化,生成的酯进行气相色谱分析。结果葡萄叶中2甲4氯、2,4-滴和2,4-滴丙酸的检测限分别为20ng/g、20ng/g和30ng/g,葡萄叶中除草剂浓度100~1000 ng/g成线性关系,空白葡萄叶中添加2甲4氯、2,4-滴和2,4-滴丙酸200ng/g的平均回收率分别为98.8%、101.3%和103.1%,回收率的变异系数分别为11.4%、11.0%和9.3%。结论本文方法检测被毒害的葡萄叶中3种除草剂是灵敏和准确的。 相似文献
158.
目的研究CO中毒腐败血、肝组织检材中CO的HS/GC/MS检测。方法用HS/GC/MS法分析碳氧血红蛋白(COHb)血的线性范围。配制10%、30%、50%、70%浓度COHb血样,分别在室温、冷藏、冷冻条件下保存,分别在当日、第4、14、45d进行测定,比较实验结果。腐败肝组织由雄性健康家兔通CO气体致死,当天解剖,家兔肝常温隔绝空气保存并放35d至腐败,期间进行不定期顶空测定分析。结果制备的COHb血在0-100%之间有良好的线性关系Y=2.4X+2.2(r=0.9995)。以此方法测定家兔CO中毒致死的COHb新鲜血的浓度和4℃下放置45dCOHb腐败血,结果表明温度对血样中COHb%的测定影响最大。采用HS/GC/MS法检测,每次只需0.25ml血样或1g肝脏,分析一次时间只需3min,均可检测出新鲜检材和常温放置45d的腐败肝组织检材CO的含量。结论HS/GC/MS法能检出CO中毒的腐败生物检材中CO。 相似文献
159.
目的建立毛细管气相色谱法定量分析酱油中有毒成分4-甲基咪唑的方法。方法酱油样品在层析柱中用二氯甲烷洗脱,洗脱液浓缩后加入N,N-二甲基苯胺作为内标,采用DB-FFAP毛细管柱分离样品,氮磷检测器测定4-甲基咪唑含量。结果方法线性范围为4.9~1.5×102μg/L;检测限为0.16μg/L;标准加入0.0102mg和0.0602mg 4-甲基咪唑的平均回收率为97.25%和99.44%。结论本文方法具有操作简便、快速、准确等优点,可用于检验酱油中的4-甲基咪唑。 相似文献
160.