Indian Drugs 48(4), 49-55 (2011). HPTLC of hydrochlorothiazide (HCZ), amlodipine besylate (AMB) and valsartan (VAL) on silica gel with ethyl acetate - methanol - 10 % ammonia 17:4:2. The hRf value was 26 for AMB, 34 for VAL and 82 for HCZ. The linearity range was 100-700 ng/band for VAL and HCZ and 50-400 ng/band for AMB.

J. Planar Chromatogr. 23, 365-368 (2010). HPTLC of palmitoyl hexapeptide (an antiwrinkle peptide) on silica gel with toluene - ethanol 9:1 in a twin-trough chamber with saturation for 30 min at room temperature (25 +/- 2 °C). The hRf was 33. Quantitative determination by absorbance measurement at 211 nm. Linearity was between 10 and 30 ng/band. The LOD and LOQ was 3 and 9 ng/band, respectively. The intra-day precision (%RSD, n = 6) was 0.9-1.5 % and the inter-day precision 0.9-1.4 %. The small %RSD obtained after small changes of the method conditions indicate the method is robust. The recovery of the method was in the range of 98.9-101.3 %.

J. Planar Chromatogr. 24, 125-129 (2011). HPTLC of plant extracts and oxyresveratrol on silica gel, prewashed with methanol, with hexane - ethyl acetate - chloroform - methanol 15:10:17:8 in a twin-trough chamber lined with filter paper and saturated for 20 min. Quantitative determination by densitometry at 327 nm. LOD and LOQ were 50 and 200 ng/band, respectively. The hRf value of oxyresveratrol was 31. Intra-day and inter-day variation (%RSD) were consistently below 5.0 %. Within-day precisions for the replicate analysis (n = 3) were in the range of 1.1-4.1 %. Day-to-day replicates (n = 9) were between 2.1-2.8 %.

J. Strait Pharm. 22 (12), 59-60 (2010). TLC of the extracts of the title traditional Chinese medicine 1) for red Ginseng, on silica gel with benzene - ethyl acetate - formic acid 20:16:3, detection by spraying with 3 % FeCl3 in ethanol and viewing under daylight; 2) for Chinese Taxillus twig, on silica gel with water-saturated toluene - ethyl acetate - formic acid 5:4:1, detection by spraying with 5 % AlCl3 in ethanol; 3) for Hawthorn, on silica gel with toluene - ethyl acetate - glacial acetic acid 24:8:1, detection by spraying with 3-10 % sulfuric acid in ethanol and heating at 105 °C until the zones were detected; 4) for Alisma orientale, on silica gel with toluene - ethyl acetate - formic acid 14:7:2, detection by spraying with acetic acid - concentrated sulfuric acid - ethanol 1:1:1, heating at 105 °C until the zones were detected and viewing under daylight. Identification by comparison with the standards of the individual drug.

Asian Journal of Chemistry 23 (5), 2046-2048 (2011). TLC of alpha- and beta-asarone in Acorus calamus on caffeine modified silica gel (with 10 % caffeine in dichloromethane and dried at 100 °C for 10 min) with toluene - ethyl acetate 93:7. The hRf value of alpha-asarone was 67 and of beta-asarone 77. Quantitative evaluation by absorbance measurement at 313 nm. The linearity was in the range of 50-1000 ng/band for beta-asarone. The alcoholic extracts of samples from different geographical regions were found to contain 0.2-0.8 % of alpha-asarone and 8.7-11.2 % of beta-asarone.

J. Planar Chromatogr. 25, 571-574 (2012). HPTLC of theanine in tea extracts on silica gel with n-butanol - acetone - acetic acid - water 7:7:2:4. Detection by dipping into a ninhydrin reagent for 3 s, followed by heating at 105 °C for 5-15 min. Quantitative determination by analysis of green channels of photographs using the CP Atlas 2.0 software. The hRf of theanine was 35. Linearity was in the range of 1.4-14 ng/zone. The intermediate/inter-day/intra-day precision was below 0.7 % (n=3). Recovery (by standard addition) was between 95.7 and 102.5 %.

J. Planar Chromatogr. 25, 262-268 (2012). HPTLC of paraquat (1), diquat (2), difenzoquat (3), mepiquat (4), and chloromequat (5) in water on silica gel with 1-propanol - methanol - 2.5 N NaCl 1:1:3. Quantitative determination by absorbance measurement between 500 and 535 nm. The hRf values of compounds (1) to (5) were 21, 30 36, 52 and 56, respectively. Limits of quantification were 5 ng/zone for (1), 2 ng/zone for (2), 25 ng/zone for (3), 15 ng/zone for (4) and 9 ng/zone for (5). Recovery rates for compounds (1) to (5) were 50.7, 65.2, 59.6, 45.1 and 33.7 %, respectively.

J. Planar Chromatogr. 25, 475-480 (2012). HPTLC of amlodipine besylate (1), hydrochlorothiazide (2) and olmesartan medoxomil (3) on silica gel with chloroform - ethyl acetate - toluene - methanol - glacial acetic acid 39:39:77:39:6. Quantitative determination by absorbance measurement at 230 nm. The hRf of compounds (1) to (3) were 31, 56 and 81, respectively. Linearity was in the range of 200-4800 ng/band for (1), 100-4000 ng/band for (2) and 200-5200 ng/band for (3). Limits of detection and quantification were 35 and 101 ng/band for (1), 20 and 59 ng/band for (2) and 48 and 144 ng/band for (2), respectively. Intermediate/inter-day/intra-day precision was below 1.0 % (n=6). Mean recovery was between 100.0 and 100.3 % for all active agents.