A simple and efficient approach to reversed-phase HPLC method screening

The development and utility of an efficient HPLC method screening strategy using only four columns for the separation of pharmaceutical compounds and related impurities is presented. The strategy established a two-column approach to enable rapid early method development, along with a four-column approach for commercial method development of the analytical methods utilized to verify the quality of drug substance or drug product. Mobile phases consisted of acetonitrile or methanol with aqueous trifluoroacetic acid for low pH screening, and ammonium hydroxide for high pH screening. Examples are provided to demonstrate the practicality and orthogonality of the method screening process. A unique system suitability check, using commercially available compounds, was incorporated as a tool for troubleshooting and for ensuring adequate system performance prior to screening. Initial testing of the strategy revealed that the columns chosen were successful in leading to assay and impurity methods for 40 pharmaceutical compounds.     

柱层析-紫外分光光度法测定复方丹参片中丹参酮的含量

目的:建立复方丹参片中丹参酮含量的测定方法。方法:采用柱层析-紫外分光光度法。样品用甲醇提取,提取液经过氧化铝柱分离出丹参酮,于269nm波长处测定其含量。结果:以丹参酮ⅡA为对照品,其线性范围为2.00～10.00μg·mL-(1r=0.9995),回收率为99.30%,RSD=0.32%。结论:该方法简单、可靠,可作为该制剂质量控制方法之一。     

人体再生复原科学的历史与发展

在开启人体再生生命计划的关键历史时期,在生命科学发展的新形势下,徐荣祥教授在第十三届全国烧伤创疡学术会议中回顾了人体再生复原科学的发展历程,讲解了人体再生复原科学(简称:器官再生科学)的核心内涵和最新学术动态,展示了人体再生复原科学的实践成果与发展方向,公布了已经取得明显再生还童效果的再生皮柱技术,该项新技术是把可吸收的再生物质导入到器官组织中,使其在局部发挥再生复原作用,进一步验证了器官再生科学可以应用于非创伤性器官的再生,从而说明了除皮肤以外的各种器官都可以在正常组织结构上再生,而非只能在缺损器官上再生。这一突破性的人体再生复原科研成果,使人类千百年来梦寐以求的再生还童梦想得以呈现。徐荣祥教授在演讲中还指出,人体再生复原科学已成为世界生命科学领域中唯一实现临床应用的造福于人类的前沿科学,它在给人类带来再生生命幸福生活的同时,也给人类创造了一个全新的再生生命世界。     

Uses of Column Technology in Blood Transfusion

Microtubes in which columns of gel or microspheres are contained have gained widespread acceptance for routine serological testing. The use of columns for blood grouping, antibody screening and identification, and compatibility testing have all been well described. Columns have also been shown to perform well in the identification of antibody immunoglobulin subclasses and in the investigation of drug induced hemolytic anemia. The development of multi skilled laboratories has been facilitated by the introduction of these techniques and anxieties about loss of traditional skills have proved to be unfounded. The development of automation able to identify, handle and interpret large numbers of column tests has also led to their introduction into busy serological laboratories. New developments to increase the range of tests for which gel columns can be used include the use of columns containing specific monoclonal antibodies for the diagnosis of paroxysmal hemoglobinuria.

The ability to easily and accurately identify irregular antibodies in patients serum associated with similarly accurate grouping and compatibility testing has led to improved patient care and management and a more efficient and effective delivery of transfusion practice.     

Development and validation of a fully automated LC method for the determination of cloxacillin in human plasma using anion exchange restricted access material for sample clean-up

In the framework of a preliminary investigation on the plasma profile of cloxacillin after oral administration, a simple and rapid LC method was developed for the direct determination of this compound in human plasma. The on-line sample clean-up was carried out using a weak anion exchanger (diethylaminoethyl groups) as restricted access material (RAM). The effects of the washing liquid pH, the ionic strength and the addition of organic modifier to the washing liquid were studied in order to obtain an efficient sample clean-up and a high recovery of cloxacillin. The separation was achieved on octadecylsilica stationary phase using a mobile phase consisting in a mixture of phosphate buffer (pH 4.0; 25 mM) and acetonitrile (72:28, v/v). The UV detection was performed at 215 nm. The most appropriate regression model of the response function as well as the limit of quantitation (LOQ) were first selected during the pre-validation step. These criteria were then assessed during the formal validation step. The LOQ was 50 ng/ml. The method was also validated with respect to analyte recovery, precision, trueness, accuracy and linearity. Finally, it was successfully applied for the analysis of the first plasma samples obtained from patients having taken an oral dose of 500 mg cloxacillin.     

大黄中大黄酚的提取、分离和纯化方法研究

目的探讨获得高纯度大黄酚的可行性。方法先用稀硫酸溶液将大黄中总蒽醌苷水解成苷元,再用热氯仿提取苷元,以碱液将氯仿液中大黄酸、大黄素、芦荟大黄素除去,并用柱层析法分离大黄酚和大黄素,经乙醇反复多次重结晶,得高纯度的大黄酚;采用高效液相色谱法测定其中大黄酚的含量。结果本方法提纯得到的大黄酚纯度达98%以上。结论本方法操作简单、重现性好、成本低、毒性小,可用于大批量生产。     

Development of a LC-LC-MS complete heart-cut approach for the characterization of pharmaceutical compounds using standard instrumentation

A total heart-cut LC–LC–MS technique is described for the analysis of pharmaceutical compounds. Utilizing ordinary LC–MS equipment, a standardized multi-dimensional, highly selective approach was developed. The system was developed on synthetic mixtures containing ten active pharmaceutical compounds. The methodology would be further deployed for the impurity characterization of batches of active chemical, process intermediates, and reference standards. Column-switching was employed to heart-cut sequential fractions from one set of LC conditions to another set of LC conditions. Two high efficiency columns, including the Merck Chromolith® C18, for fast LC–LC analysis were used. The system provides a highly automated, turnkey, multi-dimensional approach applicable to a variety of complex mixtures with little user intervention. It is envisioned that this idea could be viewed as a platform for other types of LC–LC analyses including peptide and achiral–chiral analyses.     

银杏酸的分离与银杏叶制剂中银杏酸的含量测定

目的:建立银杏酸的色谱分离和高效液相色谱定量测定方法。方法:采用氯仿提取,S iO2/Ag 柱色谱和制备液相色谱法从银杏外果皮中分离得到3种银杏酸单体,应用光谱技术鉴定了其结构,并建立了银杏叶制剂中的银杏酸含量检测的高效液相色谱方法。结果:通过结构确证,分离得到的3种单体银杏酸-Ⅰ(C13:0)、银杏酸-Ⅱ(C15:1)、银杏酸-Ⅲ(C17:1)结构与相关文献报道一致,在总银杏酸中所占比例高。结论:本法确立了银杏酸的分离纯化方法和银杏叶及其制剂中银杏酸含量的高效液相色谱测定方法,用3种单体作为对照品来定量分析能更准确测定银杏酸含量。     

Distribution of choline acetyltransferase and NADPH diaphorase in the spinal cord of the pigeon

Acetylcholine is the neurotransmitter of somatic and autonomic motor systems of the spinal cord. However, there are also intrinsic cholinergic systems which have modulatory functions. Modulatory functions have also been assigned to nitric oxide (NO). Acetylcholine is synthesized by choline acetyltransferase and NO by nitric oxide synthase, which is a NADPH diaphorase. The distribution of both enzymes in the mammalian spinal cord is well known. However, there is a lack of comparative data in avian species. Therefore, the distribution of both enzymes in the spinal cord of the pigeon was studied using histochemical and immunohistochemical methods. Aside from somatic motor neurons and autonomic preganglionic neurons choline acetyltransferase-immunoreactivity was found throughout the spinal cord in lamina III of the superficial dorsal horn and near the central canal. The location of choline acetyltransferase-positive preganglionic neurons in the centrally located column of Terni and the lack of an intermediolateral column typical of the mammalian spinal cord can be confirmed. In lumbosacral segments the axons of centrally located cholinergic neurons crossed to the contralateral side to form a tract in the ventral funiculus, which then innervates the contralateral grey substance. A dense band of NADPH diaphorase staining was found in lamina II and in centrally located neurons of all segments. Part of the centrally located neurons double-labelled for choline acetyltransferase and NADPH diaphorase. In contrast to mammals, preganglionic neurons labelled only weakly for NADPH diaphorase. Altogether, despite the divergent evolution of both classes of vertebrate intrinsic modulatory choline acetyltransferase and NADPH diaphorase systems of birds seem to be largely similar to those of the mammalian spinal cord.     

茶薪菇子实体多糖的分离纯化和抗氧化活性的测定

烘干研磨成粉的茶薪菇(Agrocybe cyclindracea)子实体用热水提取，乙醇沉淀，Sevage法去蛋白，分级沉淀，得多糖PⅠ、PⅡ、PⅢ。Pm用DEAE纤维素、SephadexG-200柱层析进一步纯化，得PⅢ’，聚丙烯酰胺凝胶电泳和葡聚糖凝胶柱层析证明PⅢ’为均一组分，分子质量为94400u。抗氧化活性的测定实验表明，PⅠ、PⅡ、PⅢ均有抗氧化活性。