J. Planar Chromatogr. 20, 447-450 (2007). HPTLC of piperine on silica gel, prewashed with methanol, with hexane - acetone 13:7 in a twin-trough chamber with chamber saturation for 5 min. Quantification by densitometry at 340 nm in absorbance mode.

59th Indian Pharmaceutical Congress C-42, 234, (2007). HPTLC of E-guggulsterone (a steroidal ketone present in oily resin of Commiphora mukul) and five marketed ayurvedic tablet formulations, on silica gel with toluene - propane-1-ol - glacial acetic acid 8:1:1. Densitometry at 254 nm. The hRf of E-guggulsterone was 61. Several marketed formulations were evaluated for E-guggulsterone, the UV spectra of the standard and that of the formulations were comparable in respect of E-guggulsterone. The TLC pattern showed several other zones corresponding to unknown phytochemicals. The method was suitable for quantitative evaluation of formulation in respect of E-guggulsterone in presence of other phyto chemicals.

J. Chromatogr. A 1187 (1-2), 250-259 (2008). Description of a simple, fast and robust temperature-controlled system for non-forced-flow micro-planar chromatography. Micro-TLC plates can be developed in horizontal position under controlled temperature and with temperature gradients between - 20 and 80 ºC. Saturated or unsaturated chamber conditions are possible and only small amounts of mobile phase are required (0.3 to 1 mL). Plate temperature equilibration is obtained within 5 to 12 min and a typical non-forced flow run can be finished within only 5 to 20 min. On the micro-plate more than 10 spots can be separated in one direction or up to 180 spots per plate for two-dimensional and multi-development runs. Demonstration of fast and efficient separation of a number of analytes including fullerenes, cyclodextrins and steroids as well as complex samples obtained from natural products and pharmaceutical formulations. Thermostated micro-planar chromatography can be applied in retention and quantification studies.

J. Chromatogr. A 1188 (2), 295-300 (2008). Determination of food dyes (tartrazine, azorubine and sunset yellow) in different products by HPTLC combined with image processing of scanned chromatograms, on 3-aminopropyl modified silica gel with isopropanol - diethyl ether - ammonia 2:2:1. Quantification by using digital processing of images with special-purpose software. The limit of detection was between 5 and 9 ng/spot and the limit of quantification was between 10 and 18 ng/spot. Recovery was between 96.4 and 102.7 %.

J. Planar Chromatogr. 21, 191-195 (2008). HPTLC of fluconazole and clotrimazole (as internal standard) on silica gel with toluene - chloroform - methanol 6:15:2. Quantitation by densitometry at 210 nm.

J. Sep. Sci. 31, 237-241 (2008). HPTLC of chlorogenic acid in green coffee beans on silica gel with ethyl acetate - dichloromethane - formic acid - acetic acid - water 100:25:10:10:11. Quantitative determination by absorbance measurement at 330 nm. The hRf value was 27 and selectivity regarding matrix was given. Linearity was between 550 and 1750 ng/spot. The limits of detection and quantification were 80 and 250 ng, respectively. Recovery was 97.1 %. The intermediate/interday/intra-day precision was between 1.06 % and 1.35 % (n=6). The data showed no statistically significant differences for HPTLC and HPLC methods.

J. Liq. Chromatogr. Relat. Technol. 31, 1959-1968 (2008). Quantitative Ag-TLC of eight samples of sunflower oil with different linoleic acid content on silica gel (impregnated by dipping into a 0.5 % methanolic solution of silver nitrate) with petroleum ether - acetone 25:1, and petroleum ether - acetone - ethyl acetate 100:5:2, and 50:3:2. Detection by consecutive treatment with bromine and sulfurylchloride vapors (30 min each) followed by heating at 180-200 °C. Quantitative determination by absorbance measurement at 450 nm. Evaluation of authenticity and possible adulteration of edible oils.

J. Liq. Chromatogr. Relat. Technol. 30, 2617-2628 (2007). TLC and HPTLC of monoterpenes, e. g. menthol and menthone from peppermint, on silica gel with toluene - ethyl acetate 3:7, 4:6, ... , 9:1, and 10:0 in a horizontal chamber. Detection with methanolic vanillin - sulfuric acid reagent and under UV 254 nm. Flavonoids from hawthorn, Passiflora incarnata, hop, cacao, as well as tea were also determined by TLC and OP TLC.