Separation Of Fuchsin Analogs Using Thin Layer Chromatography

The four analogs comprising basic fuchsin have been separated using thin layer chromatography (TLC). Mixtures spotted on reverse phase TLC plates were developed with a solution of 25% methanol, 10% ammonium hydroxide, and 65% distilled water. The R_f values of the analogs were for pararosaniline, 0.54; rosaniline, 0.41; magenta II, 0.31; new fuchsin, 0.19.     

Simple,Rapid Mycobacterium ulcerans Disease Diagnosis from Clinical Samples by Fluorescence of Mycolactone on Thin Layer Chromatography

Introduction

Mycobacterium ulcerans infection, known as Buruli ulcer, is a disease of the skin and subcutaneous tissues which is an important but neglected tropical disease with its major impact in rural parts of West and Central Africa where facilities for diagnosis and management are poorly developed. We evaluated fluorescent thin layer chromatography (f-TLC) for detection of mycolactone in the laboratory using samples from patients with Buruli ulcer and patients with similar lesions that gave a negative result on PCR for the IS2404 repeat sequence of M. ulcerans

Methodology/Principal findings

Mycolactone and DNA extracts from fine needle aspiration (FNA), swabs and biopsy specimen were used to determine the sensitivity and specificity of f-TLC when compared with PCR for the IS2404. For 71 IS2404 PCR positive and 28 PCR negative samples the sensitivity was 73.2% and specificity of 85.7% for f-TLC. The sensitivity was similar for swabs (73%), FNAs (75%) and biopsies (70%).

Conclusions

We have shown that mycolactone can be detected from M. ulcerans infected skin tissue by f-TLC technique. The technique is simple, easy to perform and read with minimal costs. In this study it was undertaken by a member of the group from each endemic country. It is a potentially implementable tool at the district level after evaluation in larger field studies.     

山黧豆毒素的薄层分离

通过对山黧豆中常见的20几种游离氨基酸薄层层析发现,其毒素ODAP的Rf值与好几种相关氨基酸的接近,而用阳离子交换柱对氨基酸抽提样进行简单的分离纯化,第一个洗脱出来的即为ODAP,这样在排除其它氨基酸干扰的情况下再进行ODAP的薄层分析将得到准确的结果。     

薄层色谱法鉴定天麻胶囊中的天麻素

为了建立天麻胶囊中主要有效成分天麻素的快速鉴定方法,根据天麻素的理化特性,使用乙醇和甲醇提取天麻胶囊中的天麻素,使用薄层色谱法进行鉴定,并与高效液相色谱法的分析结果进行比较。结果表明,薄层色谱法的鉴定结果与高效液相色谱法的检测结果一致,能较准确地鉴别天麻胶囊的真伪。本研究结果表明薄层色谱法能快速简便、准确灵敏地检测天麻胶囊中的有效成分,可作为法定鉴定方法的补充,对天麻胶囊实施快速初筛。     

Separation of Lepidopterous Sex Pheromones by Reversed-phase Thin Layer Chromatography and High Performance Liquid Chromatography

Bis(4-chloro-2-ethylphenyl) phenylphosphonate was metabolically transformed into the cor-responding cyclic ester, i.e., 6-chloro-4-methyl-2-phenyl-4/f-1,3,2-benzodioxaphosphorin 2-oxide, in houseflies in vivo. In a p-unsubstituted analog, hydroxylation at the para-position of an ester linkage occurred preferably to alpha-hydroxylation with subsequent cyclization. The cyclization was diastereomerically selective, giving predominantly the cis ester. The biological activities of synthesized and related cyclic esters were similar to but weaker than saligenin cyclic phosphorus esters lacking a methyl group at the 4-position.     

Highly Stable and Sensitive Colorimetric Visualization of Trivalent Chromium Using Amido Black 10B-Stabilized Silver Nanoparticles

Plasmonics - Here, we report a highly stable and sensitive colorimetric assay for Cr3+ based on amido black 10B-stabilized silver nanoparticles (AgNPs) as the probes. The detection mechanism is...     

薄层荧光扫描法测定花生茎中白藜芦醇的含量

本文采用薄层荧光扫描法测定花生茎中白藜芦醇含量,以氯仿-乙酸乙酯-甲酸(8∶2∶0.35)为展开剂,狭缝尺寸为3 mm×0.45 mm,在335 nm处进行扫描测定。结果表明:白藜芦醇在46.4~104.4 ng范围内线性关系良好,回归方程为:Y=7.446X 2890.328相关系数R为0.9970。该法简便,快速,精密度高,平均回收率为103.46%,相对标准偏差为0.66%(n=3)。     

Thin layer chrornatography and histochemistry of Sudan Black B

Summary Thin layer chromatography of commercial Sudan Black B on silica gel with chloroform-benzene (11) as the developing solvent reveals two blue main fractions with R_f values of 0.49 and 0.19, SBB-I and SBB-II respectively. Furthermore at least eighteen secondary fractions or impurities have been found. SBB-I and SBB-II were isolated and purified by preparative thin layer chromatography. Commercial Sudan Black B consists of about 20 p.c. SBB-I, 60 p.c. SBB-II and 20 p.c. secondary fractions.From spectrophotometrical and histochemical investigations it appeared that SBB-I stains lipids more pronounced than SBB-II; moreover SBB-I is more specific for neutral lipids than SBB-II, which fraction may also stain some proteins and acid mucopolysaccharides. Contrary to SBB-II the staining with SBB-I is fairly independent of pH. Finally, the colour of SBB-II changes under the influence of light and air, while SBB-I is much more stable.A physico-chemical study of the nature of SBB-I and SBB-II, including spectrophotometry, chromatography, infrared spectroscopy and chemical analysis revealed, that SBB-II is a basic dye, while SBB-I in spite of the structural resemblance behaves as a neutral one, dissolving therefore better in neutral lipids.As yet the chemical composition of SBB-I and SBB-II, and the relation to the scheme of synthesis of Sudan Black B has not been solved. The unspecificity of lipid staining by Sudan Black B is due to the basicity of SBB-II, and to the instability of this dye toward light and air. Moreover the some eighteen impurities may have some influence on the staining properties. The question of solubility or adsorption processes in the case of lipid staining by Sudan dyes is at least partially answered by the proposition of a dissolving fraction SBB-I and an adsorbed fraction SBB-II. The changing absorption spectra by the corresponding solvatochromic and metachromatic effects may give information about the nature of the lipids stained.     

薄层色谱和高效液相色谱联用测定暗纹东方鲀肌肉中肌肽和谷胱甘肽的含量

通过薄层色谱(TLC)与高效液相色谱(HPLC)联用技术鉴定了暗纹东方鲀(Takifugu obscurus)肌肉中存在肌肽和谷胱甘肽,同时利用高效液相色谱法测定了肌肽和谷胱甘肽(GSH)的含量。薄层层析采用的展开剂为正丁醇:乙酸:水(4∶2∶1),层析板为硅胶板。高效液相色谱利用Kromasil C18反相柱分析,流动相为10%的纯乙腈和90%含有0.05%三氟乙酸的超纯水。结果表明:通过薄层色谱和高效液相色谱鉴定了暗纹东方鲀肌肉中肌肽和谷胱甘肽,其中暗纹东方鲀肌肉中肌肽含量约213μg/g(鲜重),还原性谷胱甘肽含量约211μg/g(鲜重)。本法样品无需衍生,操作简便,适合于暗纹东方鲀肌肉中肌肽和谷胱甘肽的测定。本文为生物体内肌肽和谷胱甘肽的研究提供借鉴意义。     

A Widely Applicable Analytical System for Biological Stains: Reverse-Phase Thin Layer Chromatography

The suitability of reverse-phase thin layer chromatography using a commercial adsorbant and aqueous methanol as an analytical tool for biological stains was investigated. The wide range of applicability of this technique is shown by the fact that of 120 dyes used as biological stains, 84 of diverse chemical character were successfully chromatographed by varying only the water content of the eluent. Unsuccessful chromatography was due either to immobility or streaking. Dyes exhibiting this behavior can be identified prior to chromatography by inspection of their structural formulae. R_f values were found to be significantly correlated with the calculated partition coefficients. This relationship provides information for the identification of dye components revealed by chromatography and a discussion of its use in the chemical characterization of various dyestuffs is presented.     

Detection of Hippurate Hydrolase among Bacillus Species by Thin Layer Chromatography and other Methods

S ummary . The ability of 111 isolates of 33 species of Bacillus to hydrolyze hippurate into benzoic acid and glycine was tested. All, other than the strains classified as B. badius, B. cereus var. mycoides, B. cereus var. thuringiensis, B. macquariensis, B. medusa, B. pacificus, B. psychrosaccharolyticus and some B. macerans and B. polymyxa strains, were positive by thin layer chromatography (TLC). Of the 4 methods compared (hippurate agar, the sulphuric acid method, precipitation with ferric chloride and TLC), only the TLC procedure allowed a rapid and definite detection of the hydrolytic product, benzoic acid. The use of hippurate hydrolase as an additional diagnostic aid in the differentiation of aerobic spore-forming bacilli is discussed. Other characters were used to compare some recently described Bacillus spp. The combination B. cereus subsp. medusa n. subsp. is proposed.     

Thin Layer Chromatography of Radiolabeled Oligonucleotide Analogues: A Rapid and Sensitive Purity Assay

Abstract

Oligonucleotide analogues are being developed for use in cell culture, animals and for therapy. Prior to use it is important to have an indication of the oligomers' purity. Thin layer chromatography (TLC) has been applied to analyze hosphoromonothioate and phosphorodithioate oligonucleotides radiolabeled with either ³²P Or ¹⁴C. TLC coupled with radioactivity has been compared to Polyacrylamide Gel Electrophoresis (PAGE) and High Pressure Liquid Chromatography (HPLC). TLC is a rapid and sensitive alternative to these methods and is particularly suited for chemically modified oligonucleotides.     

Studies and critique of Amido Black 10B, Coomassie Blue R, and Fast Green FCF as stains for proteins after polyacrylamide gel electrophoresis.

The properties of amido black 10B (C.I. 20470), Coomassie blue R (C.I. 42660), and fast green FCF (C.I. 42053) as protein stains, along with a few comments on Coomassie blue G (C.I. 42655), are presented and dye impurities and their effects on protein-dye binding within gels are discussed. All three dyes produced metachromatic effects with some proteins. Problems encountered with long-term stability and fixation of certain maize seed proteins are reported along with procedures for overcoming them. The low solubility of Coomassie blue R in trichloroacetic acid prevented maximum staining and destaining within a reasonable time, whereas other solvents allowed diffusion of some proteins during staining. Coomassie blue R binds to proteins in much higher amounts than do amido black and fast green, which accounts for its sensitivity in detection of protein bands in gels. Procedures for obtaining maximum contrast with photographs are also outlined.     

Thin layer chromatography of commercial samples of amido black 10B

The tannic acid-phosphomolybdic acid-amido black (TPA) stain has been used primarily for staining hemoglobin. That different dye lots of amido black cause variable staining is documented in the literature. Nine commercial samples of amido black were investigated using thin layer chromatography; all of these dyes contained colored contaminants. Separation of contaminants was achieved using silica gel thin layer chromatography and a solvent system of 95% ethanol:90% phenol:concentrated NH4OH, 12:9:3. TPA staining of red blood cells was improved by using purified amido black.     

Profiling the Triacylglyceride Contents in Bat Integumentary Lipids by Preparative Thin Layer Chromatography and MALDI-TOF Mass Spectrometry

The mammalian integument includes sebaceous glands that secrete an oily material onto the skin surface. Sebum production is part of the innate immune system that is protective against pathogenic microbes. Abnormal sebum production and chemical composition are also a clinical symptom of specific skin diseases. Sebum contains a complex mixture of lipids, including triacylglycerides, which is species-specific. The broad chemical properties exhibited by diverse lipid classes hinder the specific determination of sebum composition. Analytical techniques for lipids typically require chemical derivatizations that are labor-intensive and increase sample preparation costs. This paper describes how to extract lipids from mammalian integument, separate broad lipid classes by thin-layer chromatography, and profile the triacylglyceride contents using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. This robust method enables a direct determination of the triacylglyceride profiles among species and individuals, and it can be readily applied to any taxonomic group of mammals.