Eurasian J. Anal. Chem. 4(1), 87-97 (2009). HPTLC of rabeprazole sodium on silica gel with acetone - water 7:30. The hRf value was 45. Densitometric quantification at 284 nm. Linearity was in the range of 400-2400 ng/band. The recovery was 99.6-101.4 %. The sample was subjected to forced degradation (acid, alkali, oxidative, thermal, photolytic). The degradation products were well separated from the main compound and the method is suitable for stability studies.

62nd Indian Pharmaceutical Congress Abstract No. F-262 (2010). TLC of carbamazepine on silica gel with ethyl acetate – toluene – methanol 5:4:1. Quantitative determination by absorbance measurement at 285 nm. The hRf value was 47. The linearity was in the range of 100-600 ng/zone with r2 = 0.9995. The limit of detection was found to be 17 ng/zone, whereas the limit of quantitation was found to be 50 ng/zone.

J. Planar Chromatogr. 27, 192-198 (2014). HPTLC of losartan (1), irbesartan (2), valsartan (3), and_x000D_ olmesartan (4) in plasma and dosage form on silica gel with chloroform - glacial acetic acid 3:1. Quantitative determination by absorbance measurement at 255 nm. The hRF values for (1) to (4) were 36, 45, 78 and 23, respectively. Linearity was in the range of 90-750 ng/zone for compounds (1) to (4). The intermediate/interday/intra-day precisions were below 3 % (n=6). The LOD and LOQ were 30 and 91 ng/zone for (1), 18 and 56 ng/zone for (2), 15 and 45 ng/zone for (3) and 30 and 92 ng/zone for (4), respectively. Recovery was between 96.4 and 99.5 % for (1) to (4).

Detection by spraying with 11 reagents. Application examples.

J. Chromatogr. 471, 407-419 (1989). Study of TLC retention behavior of a series of ß-carbolines on silica and amino-modified silica. Discussion of the retention mechanism in relation to different solute, solvent and stationary phase characteristics. Comparison of the stationary phases, TLC and HPLC techniques and various solvent selectivities. Study of the molecular structure-retention relationship by means of the group contributions to retention and the electronic constant.

J. Planar Chromatogr. 6, 238-241 (1993). TLC of quinoline, isoquinoline, 6-methyl-, 7-methyl-, and 8-methylquinoline on silica or aluminium oxide. Detection with e.g. eosin yellow, bromothymol blue, thymol blue, helasol green, spadns, and titan yellow as 50 mg / 100 mL solution in 2% aqueous sodium hydroxide solution. Best detectability obtained with helasol green.

J. Planar Chromatogr. 14, 28-33 (2001). TLC of 6 quinolones (ciprofloxacin, enrofloxacin, difloxacin, sarafloxacin, norfloxacin, flumequine) on diol-silica gel with solutions of HDEHP (1%, 2.5%, 5%) in acetone, with solutions of HDEHP (5%, 10%, 15%) in ethyl acetate, and with ethyl acetate - HDEHP - methanol 36:4:5; development in horizontal chambers. Detection under UV 254 nm; quantitation by densitometry.

Research Journal Pharm and Tech. 2(4),746-748 (2009). A validated HPTLC method is reported for simultaneous estimation of nebivolol hydrochloride and valsartan in combined dosage form. HPTLC on silica gel with ethyl acetate - methanol - 25 % ammonia. The hRf value of valsartan was 27 and of nebivolol 75.The method was linear in the range of 800-2400 ng/band for nebivolol and 200-1000 ng/band for valsartan. Densitometric quantification at 280 nm. The method was found suitable for routine quality control of the combined dosage form.