Asian J. Chem. 19(2), 1487-1493 (2007). TLC of ambroxol HCl and cetirizine HCl on silica gel with methanol - ethyl acetate - toluene - ammonia 3:10:12:1. Quantitative determination by absorbance measurement at 231 nm. The hRf value of ambroxol HCl was 78 and of cetirizine HCl 40. The calibration curve response was observed between 4 and 10 µg for ambroxol HCl and 0.4 and 0.8 µg for cetirizine HCl via peak height and area. The percent drug estimated for ambroxol HCl and cetirizine HCl from marketed formulation was 99.9, 100.2 by height and 100.8, 99.1 by area respectively. Recovery of ambroxol HCl via peak height and via peak area was 102.7 and 100.0 % respectively, and for cetirizine HCl 99.3 and 98.1 %.

Ind. J. Pharma Educ. Res. 42(1), 59-64 (2008). Curanams are an important group of formulations in ayurvedic and siddha medicine. HPTLC of sennoside A and piperine in methanolic and ethyl acetate extracts of Nilavakai Curanam on silica gel with n-hexane - ethyl acetate - formic acid - acetic acid 15:5:1:1. Quantitative determination by absorbance measurement at 254 nm. The methanolic extract of the laboratory formulation contained 0.61 % and 1.4 % piperine and sennoside A respectively, whereas the ethyl acetate extract contained 1.0 % and 4.2 %. The methanolic extract of the commercial formulation contained 0.27 % and 0.42 % and the ethyl acetate extract contained 0.27 and 0.53 % respectively. The method was linear in the range of 15-105 ng/spot and 5-30 ng/spot for piperine and sennoside A respectively. The recovery was 98.5 % for both compounds.

J. AOAC Int. 91, 750-755 (2008). HPTLC of acetylsalicylic acid and clopidogrel bisulfate ((alphaS)-alpha-(chlorophenyl)-6,7-dihydrothieno[3,2-c]pyridine-5-(4H)-acetic acid methyl ester) on silica gel using ethyl acetate - methanol - toluene - acetic acid 50:10:40:1. Quantitative determination by absorbance measurement at 235 nm.

60th Indian Pharmaceutical Congress PA-87, (2008). HPTLC of carvedilol on silica gel with toluene - chloroform - methanol - acetic acid 20:20:10:1. Densitometric evaluation at 240 nm. The method was linear in the range of 50-1000 ng/spot. The method could effectively separate the drug from its degradation products (acid, base, oxidaline, photodegradation). The kinetic studies confirmed that the drug is more degraded in alkaline medium than in acidic medium.

Science & Culture Jan.-Feb., 22-30 (2008). Isolation and identification of some unique chemical compounds is reported using chemical, chromatographic and spectroscopic methods such as GC-MS, HPTLC and HPLC. The presence of bio-organic molecules such as oxygenated dibenzo-a-pyrones (DBPs), their amino acyl conjugates (DCPs) and polyphenyl benzoquinones (PBQs) was observed in all the four samples of meteorites. HPTLC on silica gel with 1) n-butanol - acetone - acetic acid - water 7:7:2:4 for amino acids, detection with ninhydrine reagent and absorbance measurement at 610 nm; 2) n-butanol - acetic acid - water 3:1:2 for sugars, detection with p-anisidine reagent and absorbance measurement at 380 nm; 3) chloroform - methanol 9:1 for DBPs and absorbance measurement at 240 nm and 360 nm.

J. Planar Chromatogr. 22, 55-58 (2009). TLC of plaunotol in leaves of Croton stellatopilosus Ohba, on silica gel with chloroform - n-propanol 24:1 in a twin trough chamber saturated for 30 min. Quantitative determination by absorbance measurement at 220 nm. Recovery was 98.7 %. The plaunotol content of the leaves of C. stellatopilosus was highly variable (0.14 to 0.79 % w/w of dry weight).

J. Planar Chromatogr. 21, 305-307 (2008). HPTLC of tramadol hydrochloride and chlorzoxazone on silica gel, prewashed with methanol, in a twin trough chamber, saturated for 10 min, with ethyl acetate - toluene - ammonia 35:15:1. Quantitative determination by absorbance measurement at 273 nm.

Anal. Chim. Acta, 576 (2), 253-260 (2006). Description of a simple, sensitive, selective, precise and stability indicating method for determination of gatifloxacin both as a bulk drug and from polymeric nanoparticles by TLC on silica gel with n-propanol - methanol - 25 % ammonia 50:10:9. The hRf value of gatifloxacin was 60. Separation from degradation products (produced under acidic and basic conditions and upon wet and dry heat treatment) was good. Quantitative determination by absorbance measurement at 292 nm. Linearity was 400 - 1200 ng/spot, with a correlation coefficient of 0.9953. The limit of detection and quantitation was 3 and 8 ng/spot, respectively.