Anal. Chim. Acta 599 (2), 302-309 (2007). HPTLC of minocycline on silica gel (impregnated with a 10 % (w/v) solution of disodium ethylene diaminetetraacetic acid (EDTA) with a pH of 9.0) with methanol - acetonitrile - isopropyl alcohol - water 10:8:1:1. Quantitative determination by absorbance measurement at 345 nm. The limit of detection was 3.7 ng/spot, recovery was 99.2 - 100.2 %, and precision was good with a %RSD of 0.4 %. The method was able to separate all degradation products (produced by acidic and basic degradation, oxidation and photodegradation) from the pure drug.

Abstract No. 9148, IHCB (2009). HPTLC of gallic acid in Emblica officinalis (an important constituent of Triphala, a popular ayurvedic formulation) on silica gel with toluene - ethyl acetate - formic acid 10:10:3. The hRf value of gallic acid was 45. Quantitative determination by absorbance measurement at 254 nm. The method was linear in the range of 150-530 ng/spot. The extract was found to contain 7.5 mg/g of gallic acid.

J. Planar Chromatogr. 22, 109-113 (2009). HPTLC of purpurin on silica gel with toluene - ethyl acetate - formic acid 98:2:1 in a twin trough chamber saturated for 20 min at 25 +/- 2 °C. Quantitative determination by absorbance measurement at 255 nm. The limit of detection and quantification was 50 and 100 ng/band, respectively.

Asian J. of Chem. 21(9), 6999-7004 (2009). HPTLC of ursolic acid in methanolic and aqueous extracts of Ocimum sanctum (Tulsi) on silica gel with toluene - ethyl acetate - acetic acid 55:45:2 with chamber saturation. Detection by treatment with Liebermann Burchard’s reagent. Quantitative determination by absorbance measurement at 550 nm. The method was linear in the range of 100-400 ng/band. The amount of ursolic acid in aqueous and methanolic extracts was in the range of 0.2 and 0.4 %. Samples collected from different geographical regions were compared, samples from Kerala contained the highest levels of ursolic acid.

Ind. J. Pharma. Sci. 71(1), 98-100 (2009). HPTLC of artemisinin on silica gel with toluene - ethyl acetate with chamber saturation for 30 min. Quantitative determination by absorbance measurement at 520 nm. The method was linear over the range of 100-600 ng/band, recovery was in the range of 98.8-100.5 %.

J. AOAC Int. 92, 387-393 (2009). TLC of tenatoprazole - before and after acid and alkali hydrolysis, oxidation and photodegradation - on silica gel, prewashed with methanol and dried at 110 °C for 5 min, with toluene - ethyl acetate - methanol 6:4:1 in a twin trough chamber saturated with the mobile phase for 30 min at 25 °C. Quantitative determination by absorbance measurement at 306 nm. The limit of detection and limit of quantitation were 50 and 100 ng/spot, respectively.

Abstract No. F-243, 61st IPC (2009). HPTLC of isotretinoin and erythromycin on silica gel with toluene - dimethyl sulfoxide - methanol 65:2:25. Quantitative determination by absorbance measurement at 340 nm before derivatization for isotretinoin and at 410 nm for erythromycin after derivatization with 10 % sulfuric acid followed by heating at 100 °C for 15 min. The hRf value was 38 and 55 for isotretinoin and erythromycin, respectively. The linearity was in the range of 30-150 ng/band for isotretinoin and 1200-6000ng/band for erythromycin. Recovery was between 96.9 and 99.7 for isotretinoin and between 97.2 and 102.6 % for erythromycin. Intra-day and inter-day relative standard deviations for both components were <2.0 %.

60th Indian Pharmaceutical Congress PA-211 (2008). HPTLC of triamcinalone acetonide on silica gel aluminum foil with toluene - ethyl acetate - ammonia 33:67:1 %.The hRf value of triamcinalone acetonide was 38. Quantitative determination by absorbance measurement at 240 nm. The method was linear in the range of 100-2000 ng/spot; recovery was 99.5 %. The stability indicating method has been successfully applied to forced degradation studies of triamcinalone acetonide (acid, alkali, hydrogen peroxide, photo degradation thermal and neutral hydrolysis) and resolved degradation products and excipients from triamcinalone acetonide.