60th Indian Pharmaceutical Congress PA-215 (2008). HPTLC of ranitidine HCl and domperidone in combined dosage form on silica gel with ethyl acetate - methanol - ammonia 100:10:1 in a twin trough chamber saturated for 10 min. Quantitative determination by absorbance measurement at 285 nm. The method was linear in the range of 100-500 ng/µL for both compounds with a recovery of 102.5-100.8 %.

Abstract No. F-239, 61st IPC (2009). HPTLC of hydrochlorothiazide, ramipril and telmisartan on silica gel with ethyl acetate - chloroform - methanol 6:3:1. Quantitative determination by absorbance measurement at 215 nm. The method was suitable for routine quality control of combined formulations.

Indian Drugs 46(6), 493-496 (2009). HPTLC of chloroform extracts of the bark of Ficus racemosa, F. bengalensis, and F. religiosa on silica gel with toluene - ethyl acetate - formic acid 90:10:1. Detection under UV 254 nm and visible light after treatment with vanillin sulfuric acid reagent, followed by heating at 105 °C until coloration.

Abstract No. F-256, 61st IPC (2009). HPTLC of cefixime trihydrate and erdosteine in combined capsule dosage form on silica gel with ethyl acetate - acetone - methanol - water 15:5:5:3. Quantitative determination by absorbance measurement at 235 nm. The calibration curve was linear between 100 and 500 ng/band for cefixime and 150 to 750 ng/band for erdosteine. The limit of detection and quantification for cefixime was 0.37 µg/mL and 1.14 µg/mL, respectively and for erdosteine 0.33 µg/mL and 1.04 µg/mL, respectively.

J. Pharm. Biomed. Anal. 47, 841-846 (2008). HPTLC of iridoid glycosides in the aerial part of Gambhari (Gmelina arborea) with iridoid gycoside 6-0-(2”, 3”- dibenzoyl)-o-L-rhamnopyranosylcatalpol as a chemical marker for the standardization of G. arborea plant extracts on silica gel with chloroform - methanol 4:1. Quantitative determination by absorbance measurement at 240 nm and at 430 nm after derivatization with vanillin - sulfuric acid reagent. The linear working range was between 1000-5000 ng/spot with a good correlation coefficient of 0.994.

J. Planar Chromatogr. 23, 40-45 (2010). HPTLC of flavonoids (vitexin, isovitexin, orientin, isoorientin, rutin) on polyamide at 23 +/- 2°C and 40 % relative humidity with the three-component mobile phase A-B-C 33:67:8, where A is dodecyl sulfate - n-butanol - n-heptane 147:158:28, B is water, and C is formic acid. The solvent mentioned gave the best resolution of vitexin (hRf 61), isovitexin (hRf 21), orientin (hRf 28), isoorientin (hRf 34), and rutin (hRf 52). Detection by spraying with 1 % aluminium trichloride in ethanol followed by waiting for approximately 1h. Quantitative determination by fluorescence measurement at 366 nm. Precision was found to be 0.98, 0.91, 1.02, 1.04 and 0.87 % for isovitexin, rutin, orientin, isoorientin, and vitexin, respectively. Average recoveries (at three different concentrations) were between 98.9 and 100.6 % from P. pubescens, P. glauca and P. yixingensis.

J. Liq. Chromatogr. Relat. Technol. 31, 2657-2672 (2008). TLC and HPTLC of thiuram on silica gel with methanol or dichloromethane in a saturated horizontal chamber for 15 min. Detection by spraying with improved and non-improved iodine-azide, iodine, and copper(II) reagents and by evaluation under UV 254 nm. For derivatization the developed plates were sprayed with freshly prepared mixtures of sodium azide and starch solution adjusted to pH 6.0 (5 mL of 10 % aqueous sodium azide solution and 12.5 mL of 2 % aqueous starch solution were mixed and adjusted to pH 6.0 with 0.1 mol/L hydrochloric acid solution; the solution was diluted to 25 mL with water) and exposed to iodine vapor for 5 s. Quantitative analysis by scanning with an office scanner (PC scanner) and after detection with improved iodine-azide reagent densitometric measurement at 483 nm. The hRf value of thiuram was 29. LOD were 3 and 0.5 pmol per spot using a iodine-azide detection system in TLC and HPTLC, respectively. Linearity was in the range of 2-8 pmol per spot; the correlation coefficient r was 0.9981. Results obtained by use of a PC scanner were comparable to measurements using a TLC densitometer.

J. Planar Chromatogr. 23, 112-115 (2010). HPTLC of phyllanthin on silica gel (prewashed with methanol) with hexane - toluene - ethyl acetate 2:2:1 in a twin-trough chamber saturated at 25-30 °C and 40-50 % relative humidity. Quantitative determination by absorbance measurement at 206 nm. LOD was 70 ng/mL, LOQ 200 ng/mL.The linear calibration range was 200-1200 ng/mL. Repeatability (RSD, n = 3) was 0.18-0.59 % with a correlation coefficient of 0.999. Intra-day and inter-day precision studies showed the CV was less than 2.0 %, indicating the method was precise: %RSD at 200, 600, and 1200 ng/mL was between 0.43 and 1.51 % for intra-day precision, and between 0.59 and 1.73 % for inter-day precision. The intra-day recovery for 200, 600 and 1200 ng/mL was between 102.3 % and 99.9 %, and the inter-day recovery between 102.5 % and 99.9 %, respectively.