Abstract No. F-260, 61st IPC (2009). HPTLC of cefixime and cloxacillin on silica gel, prewashed with methanol, with n-butanol - methanol - water - formic acid 80:60:40:3. The hRf values were 28 and 45 for cefixime and cloxacillin, respectively. Quantitative determination by absorbance measurement at 293 nm for cefixime and 343 nm for cloxacillin. The linearity range was 150-600 ng/band for both compounds.

60th Indian Pharmaceutical Congress PA-233 (2008). HPTLC of glycyrrhizic acid on silica gel with toluene - ethyl acetate - glacial acetic acid 25:15:1. The hRf value of glycyrrhizic acid was 52, linearity was between 500-1000 ng/mL and recovery was 99.2 %. Withanolide A was separated with toluene - ethyl acetate - glacial acetic acid 20:20.1. The hRf value of withanolide A was 44, linearity was in the range of 400-1000 ng/mL and recovery was 99.4 %.

Abstract No. F-267, 61st IPC (2009). HPTLC of camylofin dihydrochloride on silica gel with chloroform - ethyl acetate - methanol - 25 % ammonia 50:30:20:1. Quantitative determination by absorbance measurement at 215 nm. Linearity was in the range of 1.5-7.5 µg/band. The proposed method is suitable for routine quality control of bulk drug and tablets.

60th Indian Pharmaceutical Congress PA-232 (2008). HPTLC of olmesartan medoxomil and hydrochlorothiazide on silica gel with methanol - toluene - ethyl acetate 5:11:4 with chamber saturation for 30 min. The hRf value of olmesartan medoxomil was 27 and of hydrochlorothiazide 44. The method was linear in the range of 300-1800 ng/spot for both drugs.

J. Chromatogr. Sci. 48 (2), 109-113 (2010). HPTLC of nebivolol hydrochloride on silica gel with toluene – methanol - triethylamine 19:6:1. The hRf value of nebivolol hydrochloride was 33. Quantification by densitometry in the absorbance mode at 281 nm. Linearity was between 500 and 3000 ng/spot with r2= 0.9994. The limit of detection and quantification was 63 and 191 ng/spot, respectively. Nebivolol hydrochloride was subjected to acid and alkali hydrolysis, oxidation, thermal degradation, and photodegradation. The degradation products were well-resolved from the main component.

Abstract No. F-247, 62st IPC (2009). HPTLC of nebivolol HCl and S-amlodipine besylate on silica gel (prewashed with methanol) with chloroform - toluene - methanol - acetic acid 50:20:1. The hRf value was 33 and 48 for S-amlodipine and nebivolol, respectively. Quantitative determination by absorbance measurement at 271 nm. The method was linear in the range of 500-2500 ng/band for nebivolol and 250-1280 ng/band for S-amlodipine, respectively.

J. Chromatogr. A 1217 (23), 3711-3715 (2010). Oligosaccharides (derived from dextran, alginate, hyaluronan and chondroitin sulfate) were characterized by matrix-assisted laser desorption and ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) directly on a normal phase TLC plate. The applied oligosaccharides were either commercially available or obtained from the polysaccharides by HCl-induced hydrolysis. TLC was followed by MALDI-TOF MS subsequent to matrix deposition. The high quality mass spectra obtained allow for unequivocal assignments. The high content of formic acid in the solvent does not cause major problems but is responsible for the partial formylation of the analyte and a minor N-acetyl loss from hyaluronan and chondroitin sulfate.

J. Planar Chromatogr. 23, 56-64 (2010). HPTLC of thirteen quinolines (quinoline, isoquinoline, 2,4-dihydroxyquinoline, 8-hydroxyquinoline, 5,6-benzoquinoline, 2,2’-diquinoline, 8-methylquinoline, 5-aminoquinoline, 1-ethylquinoline, 2-chlorquinoline, 6-nitroquinoline, 2,6-dimethylquinoline, 5-hydroxyquinoline) on cyano phase with different mobile phases prepared from mixtures of methanol, acetonitrile, 2-propanol, tetrahydrofuran, and dioxane with addition of buffer at different pH, ion-pairing reagents, or silanol blockers. Detection under UV light at 254 nm and by densitometric absorbance measurement at 254 nm. Improved peak symmetry was observed for mobile phases containing ion-pairing reagent. The most symmetrical peaks were obtained by use of mobile phase containing diethylamine as silanol blocker.