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自19世纪末期,指纹鉴定一直是世界上犯罪侦查中最有效的个体识别物证手段之一。但是,指纹遗留时间的确定至今仍是一个相对未开发的研究领域。指纹脊线的物理形貌特征和残留物的化学成分因遗留者、遗留客体和环境的不同而产生显著差异。而且,随着指纹存留条件和老化时间的不同,其物理特征和化学组成的分子种类及含量等也随之变化。研究指纹残留物的物理特征和起始化学组成以及随遗留时间的变化关系是法医科学研究的重点课题,不仅有利于发展新的指纹检测方法和技术,而且可以提升鉴别犯罪现场发现的指纹的相关性。本文主要讨论已发展的各种方法和技术,如液相色谱、荧光光谱、红外光谱、紫外-可见光谱、拉曼光谱、质谱和高分辨率成像等方法,以及这些方法在指纹残留物的物理特征和化学组成及其随遗留时间的变化关系的研究中取得的进展以及局限性。最后,对发展潜在更可靠的指纹遗留时间确定方法中面临的挑战和未来的发展趋势进行展望。 相似文献
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中药组方就是将单味中药按照一定的规律配伍成方,因剂量配伍差异会导致组方理化性质的改变,从而导致组方功效强弱、性质方面发生变化,甚至产生新的化学成分。中药组方鉴别与质量控制一直是困扰中药工作者的一个难题。指纹图谱技术具有宏观、准确、稳定等优点,已被广泛用于中药领域。中药组方指纹图谱是解决中药合理组方配伍的最有效手段,其对中药质量控制已经得到普遍关注和重视。由于指纹图谱具有整体定量功能和特征性鉴别作用,对于成分复杂的中药组方能够全面地定性与定量评价。本文就中药组方指纹图谱的研究意义与目的进行了综述,并详细阐述了组方指纹图谱的研究方法与思路,以此为中药及其组方指纹图谱研究提供参考。 相似文献
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茚三酮最初用于分析化学和生物化学中的氨基酸检测,后来被引入法庭科学领域,成为显现纸张等渗透性客体上潜指纹的最常用的试剂,具有很高的显现灵敏度。介绍了茚三酮的发现与应用历史,与氨基酸的反应过程,以及其在潜指纹显现与增强中的应用,从而可以将法庭科学的技术和原理拓展至有机化学、配位化学的教学内容。 相似文献
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利用样本成分耗散物的非线性化学指纹图谱的检测方法、条件、特点和应用 总被引:2,自引:0,他引:2
分析了适用于测定样本非线性化学指纹图谱的热力学体系和动力学模型,结果表明,在远离平衡的封闭体系和无耗散物补充的敞开体系中,阻尼非线性化学反应对样本化学成分的群集表征和整体含量分析具有重要作用.以丙酮和葡萄糖等为耗散物的阻尼B—Z振荡非线性化学反应为例,研究了反应物种及其浓度、电极类型、温度、搅拌速率、样本种类及用量等影响非线性化学指纹图谱的因素,并对指纹图谱中样本化学成分的定量信息、指纹图谱的特点和应用等进行了研究.成功提出了用于鉴别和评价样本的非线性化学指纹图谱的检测条件和方法. 相似文献
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双定性双定量相似度法评价银杏达莫注射液的高效液相色谱指纹图谱 总被引:48,自引:0,他引:48
建立了色谱指纹图谱的双定性双定量相似度评价法,并应用于银杏达莫注射液的高效液相色谱(HPLC)指纹图谱的评价。采用反相HPLC,以芦丁为参照物峰,确定了41个共有峰,建立了银杏达莫注射液的对照指纹图谱。以双定性相似度S和S′、双定量相似度C和P评价银杏达莫注射液的HPLC指纹图谱,分别考察在大峰缺失和小峰缺失两种情况下,4个相似度指标的变化特征。S能反映化学成分的分布比例,受大峰影响严重,无法反映小峰的丢失; S′对所有指纹峰等权,反映小峰缺失灵敏,二者构成双定性相似度。C能反映样品共有峰的总体含量,但受大峰影响严重,无法反映小峰的缺失; P对所有峰积分值等权,能较好地反映小峰的变动,二者构成双定量相似度。因此,由S与S′、C与P构成的双定性双定量相似度法能同时监测大峰和小峰的变动与缺失,能准确地解决色谱指纹图谱的宏观定性和定量评价问题。同时还提出了方向余弦作为对照指纹图谱的特征指纹的概念和分解相似度的概念,以此考察了各指纹峰对相似度贡献的大小及其在不同程度缺失时4种相似度的变化情况。所建立的HPLC对照指纹图谱可用于银杏达莫注射液的质量控制。 相似文献
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植物类中药中微量元素的因子分析和聚类分析 总被引:40,自引:0,他引:40
尝试利用化学计量学方法探讨微量元素含量与中药药性的相关性。对105味植物类中药42种微量元素测定数据用因子分析和聚类分析进行了多因素分析。因子分析证实了一个10因子模型合理解释这些微量元素间的相关关系;样本聚类分析证明了105株中药合理地聚类成不同组; 相似文献
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Xiaoyan Liu Wenwen Jiang Mei Su Yue Sun Hongming Liu Lei Nie Hengchang Zang 《Journal of separation science》2020,43(1):6-17
The usage of traditional Chinese medicines has expanded globally, but the data about authentication, efficacy, and safety is far from sufficient to meet the criteria supporting their use worldwide due to complexity in the composition. Fingerprinting describes integral characterization and reflects interactive aspects of complex components; therefore, it can offer the possibility of evaluating quality of traditional Chinese medicines following the overall principle. Chemometric techniques introduce multivariate analytical methods into fingerprinting to obtain more information that is useful, which is consistent with the holistic thought and plays an important role in research on the substantial basis. In this review, we will start with three aspects to expound the quality evaluation of traditional Chinese medicines based on fingerprints. The analytical techniques used in developing fingerprints including chromatographic methods, spectroscopic methods, and capillary electrophoresis are introduced. Strategies for fingerprints analysis usually based on chemometric methods including unsupervised and supervised pattern recognition are described. Applications of fingerprints for multi‐component quantification, quality control, screening of bioactive components, and fingerprint‐efficacy relationship study are also outlined. Finally, we propose challenges and future perspectives of fingerprints in quality evaluation to promote the development of modernization and internationalization of traditional Chinese medicines. 相似文献
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Although sophisticated and technologically advanced, current quality control methods for Chinese medicines (syn. Chinese materia medica or CMM) lack comprehensiveness and practicability. They are more suited for analyzing single-chemical drugs or specific, known chemical components that have already been isolated. While these methods can fully satisfy the modern scientific requirements for identity, purity and quality in the assessment of chemical drugs, they are not suitable for handling the complex chemical nature of traditional CMM whose multifunctional components along with their inherent holistic activities are frequently unknown and thus are not adequately analyzed by these methods. In order to assess properly and meaningfully the identity and quality of complex CMM (also known as Chinese herbs and Chinese herbal medicines), additional measures that can retain the traditional aspect of CMM need to be included. This requires a basic understanding of traditional Chinese medicine (TCM). 相似文献
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Alaerts G Merino-Arévalo M Dumarey M Dejaegher B Noppe N Matthijs N Smeyers-Verbeke J Vander Heyden Y 《Journal of chromatography. A》2010,1217(49):7706-7716
Identification and quality control of products of natural origin, used for preventive and therapeutical goals, is required by regulating authorities, as the World Health Organization. This study focuses on the identification and distinction of the rhizomes from two Chinese herbs, rhizoma Chuanxiong (from Ligusticum chuanxiong Hort.) and rhizoma Ligustici (from Ligusticum jeholense Nakai et Kitag), by chromatographic fingerprints. A second goal is using the fingerprints to assay ferulic acid, as its concentration provides an additional differentiation feature. Several extraction methods were tested, to obtain the highest number of peaks in the fingerprints. The best results were found using 76:19:5 (v/v/v) methanol/water/formic acid as solvent and extracting the pulverized material on a shaking bath for 15 min. Then fingerprint optimization was done. Most information about the herbs, i.e. the highest number of peaks, was observed on a Hypersil ODS column (250 mm × 4.6 mm ID, 5 μm), 1.0% acetic acid in the mobile phase and employing within 50 min linear gradient elution from 5:95 (v/v) to 95:5 (v/v) acetonitrile/water. The final fingerprints were able to distinguish rhizoma Chuanxiong and Ligustici, based on correlation coefficients combined with exploratory data analysis. The distinction was visualized using Principal Component Analysis, Projection Pursuit and Hierarchical Clustering Analysis techniques. Quantification of ferulic acid was possible in the fingerprints of both rhizomes. The time-different intermediate precisions of the fingerprints and of the ferulic acid quantification were shown to be acceptable. 相似文献
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《Journal of separation science》2017,40(13):2838-2848
An approach combining micellar electrokinetic chromatography fingerprinting with chemometrics was developed to evaluate the quality consistency of Lianqiao Baidu pills, which are traditional Chinese patent medicines composed of 19 herbs used mainly to treat skin ulcers, common cold, rheumatism, herpes, and constipation. The triangle optimization method was employed to choose a satisfactory background electrolyte, with the information index, I , as an objective function for assessing the capillary electrophoresis conditions. Then, under the optimal conditions, the micellar electrokinetic chromatography fingerprints of 28 batches of samples were established, and five marker compounds were quantitatively determined simultaneously. A limited‐ratio quantified fingerprint method was introduced to evaluate the chromatographic fingerprints both qualitatively and quantitatively. Principle component analysis revealed that the 28 batches of samples can be clustered according to different manufacturers. Moreover, the relationship between the fingerprint and the antioxidant activity was explored by orthogonal partial least‐squares regression, which provided critical medicinal efficacy information for quality control. The present study establishes a powerful and reliable method for monitoring the quality consistency of Lianqiao Baidu pill. 相似文献
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Two databases have been constructed to facilitate applications of cheminformatics and molecular modeling to medicinal plants. The first contains data on known chemical constituents of 240 commonly used Chinese herbs, the other contains information on target specificities of bioactive plant compounds. Structures are available for all compounds. In the case of the Chinese herbal constituents database, further details include trivial and systematic names, compound class and skeletal type, botanical and Chinese (pinyin) names of associated herb(s), CAS registry number, chirality, pharmacological and toxicological information, and chemical references. For the bioactive plant compounds database, details of molecular target(s), IC50 and related measures, and associated botanical species are given. For Chinese herbs, approximately 7000 unique compounds are listed, though some are found in more than one herb, the total number for all herbs being 8264. For bioactive plant compounds, 2597 compounds active against 78 molecular targets are covered. Statistical relationships within and between the two databases are explored. 相似文献
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GC–MS combined with chemometric techniques for the quality control and original discrimination of Curcumae longae rhizome: Analysis of essential oils 下载免费PDF全文
Yichen Hu Weijun Kong Xihui Yang Liwei Xie Jing Wen Meihua Yang 《Journal of separation science》2014,37(4):404-411
Curcumae longae rhizome is a widely used traditional herb in many countries. Various geographical origins of this herb might lead to diversity or instability of the herbal quality. The objective of this work was to establish the chemical fingerprints for quality control and find the chemical markers for discriminating these herbs from different origins. First, chemical fingerprints of essential oil of 24 C. longae rhizome from four different geographical origins in China were determined by GC–MS. Then, pattern recognition techniques were introduced to analyze these abundant chemical data in depth; hierarchical cluster analysis was used to sort samples into groups by measuring their similarities, and principal component analysis and partial least‐squares discriminate analysis were applied to find the main chemical markers for discriminating these samples. Curcumae longae rhizome from Guangxi province had the highest essential oil yield (4.32 ± 1.45%). A total of 46 volatile compounds were identified in total. Consistent results were obtained to show that C. longae rhizome samples could be successfully grouped according to their origins, and turmerone, ar‐turmerone, and zingiberene were the characteristic components for discriminating these samples of various geographical origins and for quality control. This finding revealed that fingerprinting analysis based on GC–MS coupled with chemometric techniques could provide a reliable platform to discriminate herbs from different origins, which is a benefit for quality control. 相似文献
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An HPLC method has been developed for the fingerprinting and quantitative analysis of cardiotonic pills. A standard fingerprint
containing 11 common peaks at three wavelengths was constructed from ten batches of pills to evaluate batch-to-batch consistency.
In addition, the amounts of three marker compounds were also determined to evaluate the quality of the quantitative analysis.
Chromatographic fingerprints at three wavelengths, along with the content of three marker compounds were found to be suitable
for quality assessment. Fufang Danshen Pian (cardiotonic tablets), a traditional dosage form is produced from three kinds
of Chinese medicinal herbs for the prevention and treatment of angina pectoris and coronary heart disease. Fufang Danshen
Pian mainly contained an additional group of liposoluble components besides salvianolic acid B from Salvia miltiorrhiza Bunge while cardiotonic pills only contained water-soluble components. Therefore, the fingerprint accompanied with marker
compounds can be used to assess the quality of the cardiotonic pills. 相似文献