J. Chromatogr. Sci. 46 (1), 4-9 (2008). Presentation of a simple and accurate stability-indicating method for the quantitative determination of ribavirin in its bulk and capsule forms by TLC on silica gel aluminium layer with chloroform – methanol – acetic acid 4:1:1. Detection by spraying with anisaldehyde reagent. Ribavirin is found to undergo degradation under all stress conditions, and the degradation products are well resolved from the pure drug with significantly different Rf values. Linearity was between 5 and 40 µg/spot (r = 0.9980). The limit of detection and of quantification was 1 and 5 µg/spot, respectively. Application of the proposed TLC method for the determination of ribavirin in pure form and in capsules, with good accuracy and precision. The results obtained by the proposed TLC method are comparable with those obtained by the official method.

J. AOAC Int. 91, 13-20 (2008). Comprehensive proposal for the validation of qualitative HPTLC methods. The steps of the validation process (method selection and optimization, stability, specificity, precision, and robustness) are illustrated with examples of identification methods: green tea leaf, ginseng root, eleuthero root, echinacea root, black cohosh rhizome, licorice root, kava root, milk thistle aerial parts, feverfew aerial parts, and ginger root. The validation protocol is a key element for structuring, managing and documenting the validation process. HPTLC is suitable for reliable identification of botanicals because it can provide chromatographic fingerprints that can be visualized and stored as electronic images. Reproducibility is improved if suitable instrumentation is used, a standardized HPTLC methodology is implemented, and methods have been validated.

Asian J. Chem. 20(7), 5514-5518 (2008). HPTLC of dutasteride on silica gel with toluene - ethyl acetate - acetic acid 14:6:1. Absorbance measurement at 210 nm. The method was linear in the range of 50-500 µg/µL. Recovery was 99.3-99.5 %. The method was suitable for routine quality control.

J. AOAC Int. 91, 1149-1153 (2008). HPTLC of berberine on silica gel prewashed with methanol using n-butanol - acetic acid - water 8:1:1 in a twin-trough chamber with chamber saturation for 5 min at 33 °C at 57 % relative humidity. Quantitative determination by absorbance measurement at 350 nm.

Asian J. Chem. 20(6), 4940-4942 (2008). HPTLC of paracetamol and tramadol hydrochloride on silica gel with ethyl acetate - toluene - ammonia 60:40:1. Absorbance measurement at 254 nm. The method was linear in the range of 0.1-0.5 µg/mL and 0.9-4.5 µg/mL for tramadol and paracetamol respectively. The recovery was 98.4-99.9 % for both compounds. The method was suitable for routine analysis.

Chromatographia 68 (9-10), 877-880 (2008). TLC of betulinic acid in Nymphoides macrospermum on silica gel with hexane - ethyl acetate - acetic acid 700:300:3. Detection by spraying with anisaldehyde-sulphuric acid reagent. Quantification by absorbance measurement at 540 nm. Linearity was in the concentration range of 100–600 ng/spot. The method is suitable for the routine quality control of Granthika Tagara.

60th Indian Pharmaceutical Congress PA-195, (2008). HPTLC of trandolapril on silica gel with toluene - ethyl acetate - methanol - formic acid 5:16:2:1. The hRf value of trandolapril was 51. Trandolapril was subjected to different stress conditions like acidic and alkaline hydrolysis, oxidation, dry heat, wet heat, neutral condition and photodegradation. The degradation products were well resolved from the pure drug. Quantitative determination by absorbance measurement at 220 nm. Linearity was between 300-1800 ng/spot. The method was suitable for routine analysis of the drug in bulk and pharmaceutical dosage form.

J. Pharm. Res. (7)4, 229-232 (2008). HPTLC of lumefantrine and artemether on silica gel with toluene - ethyl acetate - formic acid 60:60:7. Quantitative determination by absorbance measurement of lumefantrine at 267 nm and of artemether at 561 nm. The hRf value for lumefantrine was 54 and of artemether 89. Linearity was in the range of 1200-6000 ng/spot for lumefantrine and 200-1000 ng/spot for artemether. The method was successfully applied to the analysis of commercial formulations.