Showing papers on "Thin-layer chromatography published in 1975"
TL;DR: Thin-layer chromatography of urinary oligosaccharides was undertaken in patients affected with various glycoprotein storage diseases and showed the presence of compounds characteristic for each disease.
164 citations
TL;DR: A single step chromatographic procedure which separates a methyl ester mixture containing 0–6 double bonds is described, and purity of each ester recovered from the silver nitrate plate was 98–99%.
Abstract: A single step, silver nitrate thin layer chromatographic procedure which separates a methyl ester mixture containing 0–6 double bonds is described. Purity of each ester recovered from the silver nitrate plate was 98–99%. Recovery of the esters ranged from 100% for saturates to 77% for pentaenes.
118 citations
81 citations
TL;DR: The excitation and emission maxima of the model fluorescent compounds, together with the characteristic reductions in fluorescence intensity caused by alkaline pH or heavy metal coordination, provide criteria with which to examine lipid peroxidation products for the presence of the conjugated Schiff base fluorophore.
Abstract: The fluorescence excitation spectrum of model conjugated Schiff base compounds that arise from the reaction of malonaldehyde with amino acids was shown to contain a maximum at 260–280 nm in addition to the previously observed maximum at 350–390 nm. Excitation at either maximum results in emission at a single maximum at 440–480 nm. The excitation and emission maxima of the model fluorescent compounds, together with the characteristic reductions in fluorescence intensity caused by alkaline pH or heavy metal coordination, provide criteria with which to examine lipid peroxidation products for the presence of the conjugated Schiff base fluorophore. Silicic acid column chromatography and silica gel thin layer chromatography were employed to fractionate the fluorescent products of model lipid peroxidation systems and of rat testicular lipid soluble extracts. These products contained large families of compounds whose fluorescence characteristics were the same as those of the Schiff base floorophores. The fractionation methods used enabled more thorough fluorescence characterization of many of the products of lipid peroxidation, but the fluores-cence criteria available do not provide definitive proof of structure.
64 citations
60 citations
TL;DR: Silica gel 60 F254 pre-coated plates for nanogram-scale thin-layer chromatography were developed for high-performance thin layer chromatography (HPTLC) on the basis of silica gel of pore size 60 A as discussed by the authors.
59 citations
TL;DR: In this article, a method was described by which phenolic acid compounds occurring in plant material can be separated on a polyamide column after suitable hydrolysis, and the mixture of phenolic acids was also separated on silica gel G thin-layer plates.
55 citations
TL;DR: From the data presented the H active substance very probably can be regarded as the immediate precursor of the B-I gly cosphingolipid from human B erythrocyte membranes.
55 citations
TL;DR: A method has been developed in which the human urinary prostaglandin metabolites are converted into stable prostanoic and prostanediotic acid homologues, to yield dimethyl tetranorprostanedioate as the major product of human prostaglandsin metabolism.
51 citations
43 citations
TL;DR: In this article, various organic compounds were separated by thin-layer cromatography on silica gel sintered glass ceramic sticks with flame ionization detector scanning, and they were successfully detected in amounts of 10−6-10−7 g per spot.
TL;DR: Higher amounts of spermidine and spermine were found in the urines of cancer patients compared to the values of these substances in normal urine.
TL;DR: In this article, a new and sensitive method for quantification of γ-hydroxybutyric acid (GHB) and its lactone precursor (GBL) was developed and successfully utilized to determine the endogenous content of these compounds in a single rat brain.
TL;DR: Methyl esters prepared from the seed oil of the conifer Taxus baccata L. were found by gas liquid chromatography to contain 12% of a component which, when isolated by preparative thin layer chromatography, was identified ascis-5,cis-9-octadecadienoic acid.
Abstract: Methyl esters prepared from the seed oil of the coniferTaxus baccata L. were found by gas liquid chromatography to contain 12% of a component which, when isolated by preparative thin layer chromatography and characterized by mass spectrometry, ozonolysis and nuclear magnetic resonance, was identified ascis-5,cis-9-octadecadienoic acid.
TL;DR: In this paper, the relationship between the RM values of a number of aromatic nitro compounds and the composition of the solvent (moving phase) is interpreted in terms of an adsorption model.
Abstract: SummaryThe relationship between the RM values of a number of aromatic nitro compounds and the composition of the solvent (moving phase) is interpreted in terms of an adsorption model. In accordance with this model, linear RM vs. log XS plots were obtained (XS is the mole fraction of the polar solvent) in wide composition ranges, the slopes of the plots being related to the molecular mechanism of adsorption and thus to the molecular structure of the chromatographed solute. The slopes indicate one-point attachment of the samples with one polar group and predominant two-point attachment of the samples with two or more polar groups (−NO2, −NH2, −OH). As in the case of the systems investigated in the previous papers of this series, the RM vs. log XS plots tend to spread fanwise with dilution of the polar solvent (improved selectivity).
TL;DR: Deposition limits for all the compounds studied were in the 0.1 mug/g feces range and Quantitation was possible in the mug/G range with an estimated accuracy of plus or minus 10%.
TL;DR: The elongation capacity of Quaking microsomes is reduced to 30% of the normal value and phosphotransacetylase was added to reduce the de novo microsomal system and the radioactive fatty acids synthesized were identified by thin layer chromatography and gas chromatography with automatic counting of the eluate.
TL;DR: Polyacrylamide-gel electrophoresis of low molecular weight DNS-peptides was performed in the presence of 0.1% sodium dodecyl sulfate and 8 m urea, and a linear relationship between molecular weight and mobility was obtained over a molecular weight range of 1,000–12,000.
TL;DR: Several 2,4-diaminopyrimidines which inhibit the enzyme dihydrofolate reductase are quantitated following extraction and separation on silica gel thin-layer chromatographic plates with a scanning instrument for the measurement of as little as 10 ng/ml of these compounds in biological fluids.
TL;DR: Histological examination of the tissues revealed some degeneration and edema, but significant spermatogenesis and normal complement of Leydig cells, and chromatographic separations employed enabled a more definitive fluorescence characterization of the lipid soluble pigments known to accumulate in tissues with age and as a result of lipid peroxidation.
Abstract: Lipid soluble fluorescent pigments from human testis were fractionated by silicic acid column chromatography and silica gel thin layer chromatography. Fluorescence analyses revealed a family of at least 3 compounds with similar fluorescence properties, including excitation and emission maxima, reversible fluorescence quenching by alkaline pH, and fluorescence quenching by heavy metal chelation. These fluorescence characteristics strongly indicated the presence of the conjugated Schiff base fluorophore-N=C-C=C-N-. The chromatographic separations employed enabled a more definitive fluorescence characterization of the lipid soluble pigments known to accumulate late in tissues with age and as a result of lipid peroxidation. Total lipids and fatty acid composition of the total lipids were determined. Polyenoic acids constituted about 40% of the total fatty acids. Histological examination of the tissues revealed some degeneration and edema, but significant spermatogenesis and normal complement of Leydig cells.
TL;DR: Applications of tubular thin-layer chromatography (TTLC) in the quantitative analysis of fish liver oils are described and typical examples of the use of this method are outlined.
Abstract: Techniques used in the quantitative evaluation of thin-layer chromatograms are compared. The quantitation of tubular thin-layer chromatograms by means of vapor-phase detectors is emphasized, and typical examples of the use of this method are outlined. Applications of tubular thin-layer chromatography (TTLC) in the quantitative analysis of fish liver oils are described.
TL;DR: Both the glucosyl transferase and the acyltransferase have been solubilized with Triton X-100 and partially purified by chromatography on Sephadex G-200 and the products thus have been identified as monoglycosyldiglyceride and diglycosyLDiglycerides.
Abstract: A particulate enzyme fraction fromMycobacterium smegmatis catalyzed the transfer of14C-glucose from UDP-14C-glucose into neutral glycolipids. The two major radioactive components were purified by column chromatography on 0-diethylamino ethyl cellulose (acetate) and thin layer chromatography on silica gel in several solvents. The first product yielded a water-soluble component upon saponification, which had a hexoseglycerol ratio of 1∶1 with all of the hexose being identified as glucose. The second product yielded a water-soluble component upon saponification which contained hexose and glycerol in a 2∶1 ratio and, in addition to glucose, contained lesser amounts of mannose and galactose. Palmitate and oleate were the predominant fatty acids and were present in equimolar amounts. The products thus have been identified as monoglycosyldiglyceride and diglycosyldiglyceride. The diglycosyldiglyceride could also be labeled with14C-galactose when UDP-14C-galactose served as the donor, but the monoglycosyldiglyceride was only slightly labeled with14C-galactose. Membrane fractions from mung bean seedlings catalyzed the transfer of14C-glucose from UDP-14C-glucose into a neutral glycolipid which has been purified by thin layer chromatography and analyzed by combined gas liquid chromatographymass spectrometry. It was determined to be a steryl glucoside with the two major sterol components being β-sitosterol and stigmasterol linked to β-D-glucose. Particulate fractions from developing cotton fibers also catalyzed the formation of steryl glucosides and, in addition, they catalyzed the esterification of steryl glucosides at the 6 position of glucose with fatty acids (primarily palmitate and oleate) from an endogenous acyl donor. Both the glucosyl transferase and the acyltransferase have been solubilized with Triton X-100 and partially purified by chromatography on Sephadex G-200. The acyltransferase activity was reconstituted by the addition of the steryl glucoside and a phospholipid acyl donor.
TL;DR: Interfering nonpolar lipid material was removed from the acetone extracts of several samples of benign hyperplastic prostate tissue and the results indicated that 5α-dihydrotestosterone is usually the most predominant of the steroids measured, and that of the 5 α-androstanediols, only the 3α, 17β and 3β, 17 β isomers occur in measurable concentration.
Abstract: Interfering nonpolar lipid material was removed from the acetone extracts of several samples of benign hyperplastic prostate tissue. Endogenous steroids were separated by preparative thin-layer chromatography into fractions containing testosterone, 5α-dihydrotestosterone and the 5α-androstane-3, 17-diols, and concentrations of these steroids were measured by molecular ion monitoring of suitable derivatives at a resolution of 8500 to 10 000 during combined gas chromatography mass spectrometry. The sensitivity and specificity of this procedure allowed unequivocal detection of the steroids of interest at the femtomole level and the incorporation of epimers as internal standards enabled accurate quantitative measurements. The results indicated that 5α-dihydrotestosterone is usually the most predominant of the steroids measured, and that of the 5α-androstanediols, only the 3α, 17β and 3β, 17β isomers occur in measurable concentration, with the former usually predominant.