Thin-layer chromatography

About: Thin-layer chromatography is a research topic. Over the lifetime, 7494 publications have been published within this topic receiving 124179 citations. The topic is also known as: TLC.

Glutathione conjugates. Immobilized enzyme synthesis and characterization by fast atom bombardment mass spectrometry.

Abstract: Glutathione transferase activity was shown to be present in an immobilized preparation of microsomal protein. Chlorodinitrobenzene, ethacrynic acid, captopril, styrene oxide, and iminocyclophosphamide were found to be substrates, each providing a different kind of electrophilic functional group for conjugation. The glutathione conjugates were characterized by thin layer chromatography (visualized by reaction with ninhydrin) and by high pressure liquid chromatography. A variety of conditions was evaluated for analysis of these glutathiones by fast atom bombardment mass spectrometry.

Measurement oftrans and other isomeric unsaturated fatty acids in butterand margarine

Abstract: A procedure is described for gas liquid chromatographic determination of cis andtrans isomers of unsaturated fatty acids after fractionation of the saturated, monenoic, dienoic, and polyenoic fatty acid methyl esters by argentation thin layer chromatography. To test its reliability, the procedure was used for quantitative measurement of transisomers of unsaturated fatty acids in a known mixture of simple triglycerides containing saturated fatty acids from 4:0 to 24:0 andcis andtrans isomers of 14:1. 16:1, 18:1, and 18:2. Results of the analyses of five margarine and five butter samples are presented, together with results of infrared spectrophotometric analyses fortrans fatty acid concentrations, ultraviolet spectrophotometric analyses for conjugated fatty acid concentrations, and enzymatic analyses forcis-cis-methylene interrupted fatty acid concentrations. The combined argentation thin layer and gas Chromatographic procedure is suitable for determination of the principal fatty acids in complex food lipids such as milk fat.

Alfalfa saponins and sapogenins: Isolation and quantification in two different cultivars

Abstract: The chemical characterization of the saponins and sapogenins isolated from roots and aerial parts of two alfalfa cultivars with differing saponin content is reported. A procedure for the extraction and quantification of saponins is described, and the identification of the major components of the saponin mixture has been performed using thin layer chromatography and high performance liquid chromatography. Characterization, using gas chromatography (GC) and GC/mass spectral analysis, of sapogenins released following acid hydrolysis allowed the identification of medicagenic acid, hederagenin, soyasapogenols B, C, D, E and F as the major compounds, together with oleanolic acid. Quantitative analysis of the sapogenins in aerial parts and roots of the two cultivars is reported and discussed.

Simple and rapid determination of ferulic acid levels in food and cosmetic samples using paper-based platforms.

Abstract: Ferulic acid is an important phenolic antioxidant found in or added to diet supplements, beverages, and cosmetic creams. Two designs of paper-based platforms for the fast, simple and inexpensive evaluation of ferulic acid contents in food and pharmaceutical cosmetics were evaluated. The first, a paper-based electrochemical device, was developed for ferulic acid detection in uncomplicated matrix samples and was created by the photolithographic method. The second, a paper-based colorimetric device was preceded by thin layer chromatography (TLC) for the separation and detection of ferulic acid in complex samples using a silica plate stationary phase and an 85:15:1 (v/v/v) chloroform: methanol: formic acid mobile phase. After separation, ferulic acid containing section of the TLC plate was attached onto the patterned paper containing the colorimetric reagent and eluted with ethanol. The resulting color change was photographed and quantitatively converted to intensity. Under the optimal conditions, the limit of detection of ferulic acid was found to be 1 ppm and 7 ppm (S/N = 3) for first and second designs, respectively, with good agreement with the standard HPLC-UV detection method. Therefore, these methods can be used for the simple, rapid, inexpensive and sensitive quantification of ferulic acid in a variety of samples.