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. Milojković-Opsenica , Fingerprinting of Serbian, Slovenian and Croatian Propolis Using HPTLC and Pattern Recognition Methods , International Symposium for High-Performance Thin-Layer Chromatography, Lyon, 2 – 4 July 2014, Book of Abstracts, p. 9

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, Sensitive and accurate estimation of losartan potassium formulation by high-performance thin-layer chromatography , Pharm. Methods 2 ( 2011 ) 95 – 98 . [26] A

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High-performance thin-layer chromatography (HPTLC) and HPTLC–mass spectrometry (MS)/(MSn) methods for analyses of phenolic acids (chlorogenic acid, rosmarinic acid, protocatechuic acid, gallic acid, syringic acid, ellagic acid, trans-cinnamic acid, o-coumaric acid, m-coumaric acid, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid) were developed. Separation was performed on HPTLC silica gel plates with and without fluorescent indicator (F254) in a saturated twin-trough chamber using n-hexane–ethyl acetate–formic acid (12:8:2, v/v) as the developing solvent. The developed HPTLC method is also suitable for the preliminary screening of some flavonoids (flavone, apigenin, luteolin, chrysin, quercetin, myricetin, kaempferide, kaempferol, hesperetin, naringenin, pinocembrin), although some interferences of phenolic acids with flavonoids were observed. The effect of pre-development on the HPTLC analysis of phenolic acids on the detection by densitometry and mass spectrometry was also explored. Pre-development of the plates with chloroform–methanol (1:1, v/v) decreased the intensity of secondary front like dark band that appeared at R F 0.7 on unpre-developed plates and enabled densitometric evaluation of phenolic acids at 280 and 330 nm. To eliminate severe spectral background observed during HPTLC–MS analysis, caused by the presence of an acidic modifier in optimized developing solvent, two pre-developments of the plates (1st methanol–formic acid 10:1, v/v and 2nd methanol) were applied. This resulted in a substantial decrease in the intensity of the background signals of sodium formate clusters and considerably improved the analysis of phenolic compounds. The applicability of the developed HPTLC and HPTLC–MS/(MSn) methods was confirmed by analyses of different complex matrix samples, e.g., propolis, roasted coffee, and rose hip crude extracts.

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. [9] P.D. Sethi , HPTLC, High Performance Thin-Layer Chromatography , CBS Publishers and Distributors , New Delhi , 1996 . [10

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. Crawford , B. Musselman , Planar chromatography meets direct ambient mass spectrometry: current trends , International Symposium for High-Performance Thin-Layer Chromatography , Lyon , 2-4 July 2014 ; Abstract O–9

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The paper presents the application of post-chromatographic iodine-azide reaction for the determination of three thiouracils (6-benzyl-, 6-methyl-, and 6-propyl-2-thiouracil) in high-performance thin-layer chromatography (HPTLC). The HPTLC plates developed by methanol were sprayed with a freshly prepared mixture of sodium azide, potassium iodide, and starch solution adjusted to pH 5.5, and exposed to iodine vapour for 5 s. Because of the induction properties of the C-S and C=S bonds of thiouracil molecule in the iodine-azide reaction, the spots became visible as white spots on a violet-brown background.Scanning of the HPTLC plates was performed on a PC scanner and analysed by TLSee software. Determination range was 7–16 pmol per spot, 80–160 nmol per mL of urine, or 133–266 nmol per 1 mL of serum.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Kit-leong Cheong, Ding-tao Wu, De-jun Hu, Jing Zhao, Kai-yue Cao, Chun-feng Qiao, Bang-xing Han and Shao-ping Li

Multiple species of ginseng are well-known Chinese medicinal herbs. The glycome of Panax species has various beneficial effects; however, studies related to their systematic profiling are very limited. Therefore, the systematic profiling of the glycome of Panax species was investigated in this study. The sugars from different locations and different species of Panax (Panax ginseng, Panax quinquefolium, and Panax notoginseng) were prepared by microwave-assisted extraction. Free mono- and oligo-saccharides were identified by high-performance thin-layer chromatography (HPTLC). Furthermore, polysaccharides were compared and characterized by using saccharide mapping based on HPTLC analysis. The results showed that the mono- and oligo-saccharide in Panax species were similar, including the glucan and pectin type of polysaccharides in different locations and different species of Panax, respectively. The data are helpful to better understand the glycome of different species of Panax and may contribute to rational usage of polysaccharides from Panax species.

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G.E. Morlock , High-Performance Thin-Layer Chromatography Mass Spectrometry for Analysis of Small Molecules, in: M.S. Lee (ed.) Mass Spectrometry Handbook, John Wiley & Sons, Inc., Hoboken, NJ, 2012

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A high-performance thin-layer chromatography (HPTLC) method for the analysis of seven fructooligosaccharides (FOS, DP3-9) in Morinda officinalis How. (M. officinalis) and Arctium lappa Linn. (A. lappa) has been established. The chromatographic analysis was developed twice with a mobile phase consisting of n-butanol-isopropanol-water-acetic acid in volume composition 7:5:2:1 and obtained on silica gel 60 plate. The chromatograms were visualized with 1-naphthol-sulfuric acid reagent. Densitometric detection was performed in visible light at 585 nm for seven FOS. The analytical range was set as 131–1050 ng for FOS. Calibration was linear within the selected range (R 2 > 0.9901). The developed method was applied for the simultaneous determination of seven FOS in M. officinalis and A. lappa. The results indicated that the contents of FOS are variant in different M. officinalis samples, but constant in different A. lappa samples. This HPTLC method was found to be simple, stable, and reproducible. Hence, the developed HPTLC method would be an important tool for the quality control of FOS in medicinal plants.

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Flexible packaging films, lids of glass jars, elastic toys, or medical commodities made of poly(vinyl chloride) contain different plasticizers, which tend to migrate out of the respective product. To test compliance to regulations, the content of plasticizers and their migration properties have to be determined analytically. With a rapid high-performance thin-layer chromatography (HPTLC) method it was able to quantify phthalic acid esters, diisononyl cyclohexane-1,2-dicarboxylate, sebacates, citrates, adipates, and epoxidized soybean oil (ESBO) simultaneously. Chromatography was performed on HPTLC silica gel glass plates, and detection was enabled by dipping the plate into primuline solution. ESBO could be quantified after a newly introduced lipase treatment and chromatography of the epoxidized fatty acids. Validation was performed by analyzing self-made plastisols, showing good recoveries and standard deviations. Limits of detection and quantification generally were approximately 10–20 and 30–60 ng per zone, respectively, but the detection of ESBO required 70 ng per zone. Thus, plasticizers in PVC samples could be quantified even if they were present as contamination at low concentrations.

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