Abstract No. C-338, 61 IPC (2009). HPTLC of gallic acid and piperine in combined formulation on silica gel with toluene - ethyl acetate - formic acid 16:8:1. Quantitative absorbance measurement at 320 nm. The method was linear in the range of 200-800 ng/band for gallic acid and 50-350 ng/band for piperine.

J. Planar Chromatogr. 23, 180-183 (2010). TLC of chamomile extracts on silica gel with benzene - ethyl acetate 19:1 or chloroform - methanol - water 40:10:1 in an unsaturated chamber. Detection at 254 and 366 nm. For bioautographic evaluation bioluminescent Bacillus subtilis or Pseudomonas syringae pv. maculicola were used; visualization by dye a reagent was achieved by dipping the plate in an aqueous solution of MTT. Quantitative determination by densitometric scanning at 300 nm (before biological detection) or at 590 nm (after visualization of the bioautogram with MTT).

Abstract No. C-454, 61st IPC (2009). HPTLC of ursolic acid and luteolin from aerial parts of Lippia nodiflora on silica gel with toluene - ethyl acetate - formic acid 70:30:3. The hRf value of luteolin was 34 and of ursolic acid 85. Densitometric analysis at 254 nm for luteolin and at 530 nm for ursolic acid after derivatization with natural products reagent followed by PEG reagent. The recovery of both marker components was in the range of 98.6-100.5 %.

The Open Nutraceuticals Journal 2, 2-6 (2009) A TLC method using a micellar solution of sodium dodecyl sulfate (SDS) as mobile phase has been developed for identification of four herbals present in Jatiphaladya, a powdered herbal formulation containing Cannabis sativa, Myristica fragrans, Piper longum, and Embleia ribes. The formulation was extracted with 80 % ethanol. TLC on laboratory made plates coated with silica gel and activated at 100 °C for 60 min, with a 5 % solution of SDS as mobile phase. The resolved spots were identified by spraying with a 2 % solution of vanillin in 5 % methanolic sulfuric acid. Spots corresponding to different herbals were well resolved. Different detection reagents were evaluated, i.e. iodine, vanillin sulfuric acid, and anisaldehyde-sulfuric acid. Vanillin sulfuric acid reagent was found to be the most sensitive. Of the different surfactants used, anionic, cationic and nonionic, SDS was found to be most suitable. The most suitable pH of the mobile phase was pH 4.2-5.7, it provided optimum resolution of zones.

J. Sep. Sci. 34, 749-760 (2011). HPTLC of (-)-epicatechin (1), (-)-epicatechin gallate (2), (-)-epigallocatechin gallate (3), caffeine (4), rutin (5), quercetin (6), gallic acid (7), ellagic acid (8), caffeic acid (9), and ferulic acid (10) in the leaves of green tea (Camellia sinensis) and guava (Psidium guajava) on silica gel with toluene – acetone – formic acid 5:4:1 for compounds (1) - (6) and toluene – ethyl acetate – formic acid – methanol 15:15:4:1 for compounds (7) - (10). Quantitative determination by absorbance measurement at 282 nm for compounds (1) - (6) and 285 nm for compounds (7) - (10). The hRf values of compounds (1) - (10) were 49, 37, 26, 60, 8, 66, 49, 34,62 and 70, respectively. Linearity was between 100-350 ng/band for compounds (1) - (5), 66.6-233.2 ng/band for compound (6) and between 50-300 ng/band for compounds (7) - (10). The limits of detection were found to be 60 ng/band for compounds (1) - (3), 30 ng for compounds (4), (5) and (8), 40 ng/band for compound (6), 20 ng/band for compound (7) and 10 ng/band for compounds (9) and (10). The limits of quantification were 100 ng/band for compounds (1) - (3), 60 ng/band for compounds (4) - (7), 30 ng/band for compounds (9) - (10), and 75 ng/band for compound (8). Inter- and intraday precisions were below 1.50 % and 2.84 %, respectively. Recoveries were found in the range of 95-100 %.

Chinese J. Ethnomed. Ethnopharm. (23), 61-64 (2010). Optimization of the sample preparation procedure for Herba Saururi chinensis 1) by ultrasonication with methanol for 60 min; 2) by ultrasonication with methanol for 20 min and filtration through neutral alumina column with methanol; 3) by reflux extraction with 80 % methanol for 60 min and extraction with diethyl ether; 4) by ultrasonication with ethanol for 60 min; 5) by ultrasonication with methanol - 25 % hydrochloric acid 4:1 for 60 min and extraction with ethyl acetate. Procedure 5) was best suited. TLC on silica gel 1) with petroleum ether (60-90 °C) – acetone 5:2, and detection by spraying with 10 % sulfuric acid in ethanol and heating at 105 ºC until the zones appear; 2) with toluene – ethyl acetate – formic acid 5:2:1, and detection by spraying with 1 % AlCl3 in ethanol and evaluation under UV 366 nm; 3) with n-hexane – ethyl acetate – formic acid 70:50:8, and detection by spraying with 1 % AlCl3 in ethanol, heating at 105 ºC and evaluation under daylight or under UV 366 nm; 4) with toluene – ethyl acetate – formic acid 5:4:1 with chamber saturation with hydrochloric acid vapor, detection under daylight or UV 366 nm.

Planta Med. 75, 1000 (2009). TLC and HPTLC of Mezereon (Daphne mezereum) bark extracts and scopoletin, umbelliferone, mezerein, and daphnetoxin on silica gel with various mobile phases containing toluene, ethyl acetate, and formic acid at different proportions. Detection under UV 254 and 366 nm and visible light. The applied procedure may be proposed for an updated and optimized TLC identification test of the homeopathic monograph of Daphne mezereum L.

Ham. Ex D. Don, Myricaceae. J. Planar Chromatogr. 23, 326-331 (2010). HPTLC of myrecitin and stem bark extracts on silica gel with toluene - ethyl acetate - formic acid - methanol 15:15:3:2. Quantitative determination by absorbance measurement at 268 nm. Linearity was between 0.4-2.0 µg/band. The limits of detection and quantitation were 93 ng and 284 ng/zone. The intra-day and inter-day precision of the method was in the range of 0.14-0.55 %. The recovery of myrecitin at three concentrations was in the range of 98.9-100.1 % and the average recovery was 99.3 %.