Phytochem. Anal. 21, 174-179 (2010). HPTLC of tiliroside (1), methyl brevifolincarboxylate (2), and ellagic acid (3) in the aerial parts of Potentilla species on silica gel with toluene - ethyl formate - formic acid 6:4:1. Quantitative determination by absorbance measurement at 320 nm for (1), 287 nm for (2), and 280 nm for (3). The hRf values of (1), (2) and (3) were 9, 13, and 20, respectively. Linearity was between 50 and 500 ng/zone for (1), 50 and 520 ng/zone for (2), and 52 and 500 ng/zone for (3). The intra- and inter-day precisions (expressed in terms of CV %) were observed in the ranges 2.5-9.0 % and 2.4-11.1 %, respectively. LOD for (1) to (3) were 5, 10 and 34 ng/zone, respectively, while LOQ were 27, 17 and 44 ng/zone, respectively. The average recovery of (1), (2) and (3) was 101.1, 82.2 and 94.0 %, respectively.

Application to the detection of antimicrobial compounds from Cordia gilletii De Wild (Boraginaceae). J. Planar Chromatogr. 23, 245-249 (2010). TLC of methanol extracts of Cordia gilletii on silica gel with dichloromethane, dichloromethane - methanol 9:1 or 4:1, or petroleum ether - diethyl ether - acetic acid 90:10:1. Detection by spraying with 1 % vanillin in ethanol followed immediately by 10 % ethanolic sulfuric acid, and heating at 105 °C for 10 min. For bioautography, 1 mL of 0.5 McFarland microorganism suspension was diluted with 9 mL of the tested mixture of Mueller-Hilton broth and agar 9:1) at 37 °C. After distribution of the inoculated mixture over the plate and solidification of the medium at ambient temperature, the plate was incubated overnight at 37 °C. The bioautogram was subsequently sprayed with an aqueous solution of MTT 0.8 mg mL-1 and incubated at 37 °C for 4 h. Also application of the Bioluminex assay (a TLC detection method based on the natural bioluminescence of the non-pathogenic bacteria Vibrio fischerii). The bioluminescent bacterial coating was visualized by use of the Bioluminizer.

Acta Chromatographica 22 (2), 259-265 (2010), DOI:10.1556/AChrom.22.2010.2.8. Description of a new, simple, precise, and accurate method for quantification of (-)-epicatechin in the leaves of Cassia fistula by HPTLC on silica gel with toluene – ethyl acetate – formic acid – methanol 205:3:1:1. Quantification by densitometry at 280 nm. The linearity was in the range of 200–800 ng/band. Method precision was 1.4 %RSD and instrumental precision 1.1 %RSD. Recovery was 98.1 % and specificity regarding matrix was given.

J. Ethnopharmacol. 139, 142-148 (2012). HPTLC of 1,2-dihydroxy-3-pentadec-8-enylbenzene (A) and 1,2-dihydroxy-3-pentadeca-8,11-dienylbenzene (B) in the fruits of Semecarpus anacardium L. f. (Anacardiaceae) on RP-18 with acetonitrile - water 199:1. Detection by spraying with anisaldehyde - sulfuric acid reagent. The hRf values of (A) and (B) were 31 and 42, respectively. The method was combined with ESI-MS and NMR for compound identification.

Planta Med. 74, 1749-1750 (2008). Analytical and preparative TLC of a new monoterpene alkaloid plumerianine, (R)-4’-{(S)-1-hydroxyethyl)-5,6-dihydro-5’H-spiro[cyclopenta[c]pyridine-7,2’-furan}-5’-one, the iridoid 15-demethylplumeride, lupeol, uvaol, and ursolic acid on silica gel with toluene - ethyl acetate 8:2 or 8:3 and chloroform - methanol 9:1. Detection by spraying with vanillin-sulfuric acid reagent.

J. Planar Chromatogr. 24, 376-380 (2011). HPTLC of stem bark extracts from D. melanoxylon and lupeol and betulin on silica gel, prewashed with methanol, with ethyl acetate - hexane 9:41 with chamber saturation for 3 min at 29 +/- 4 °C and 65 +/- 5 % relative humidity. The hRf value was 46 and 25 for lupeol and betulin, respectively. Quantitative determination by densitometry in absorption mode at 560 nm for lupeol and 510 nm for betulin. Detection by derivatization with 5 % methanol-sulfuric acid reagent. The LOD and LOQ was 40 and 100 ng/zone for lupeol and 50 and 100 ng/zone for betulin, respectively. The instrument precision and repeatability (n = 6) were 0.8 and 1.3 % for lupeol and 1.1 and 1.2 % for betulin, respectively. The linearity range was 100-500 ng/zone for both lupeol and betulin. The intra-day and inter-day precision was 1.1-1.7 % and 1.3-2.0 % for lupeol and 0.8-1.9 % and 1.9-2.2 % for betulin.

Planta Med. 77, 271-276 (2011). Analytical and preparative TLC of limonoids and quinoline alkaloids (1’,2’-didehydro-7,8-dimethoxyplatydesmine, 3-chloro-8,9-dimethoxygeibalansine, dasylactone A, dasylactone B, dictamnine, 7,8-dimethoxymyrtopsine, isofraxinellone, fraxinellone, obacunone, limonoic acid, rutaevine, and rutaevine acetate) on silica gel with chloroform - methanol 30:1, 10:1 and 6:1. Detection under UV 254 nm and by spraying with 98 % sulfuric acid - ethanol 1:19 followed by heating.

Asian Journal of Chemistry 23(5), 1917-1921 (2011). TLC of concentrated methanolic extracts of a polyherbal ayurvedic syrup formulation (containing vasaka as main ingredient) on silica gel with methanol - toluene - dioxane - 25 % ammonia 2:2:5:1. The hRf value of vasicine was 74. Quantitative evaluation by absorbance measurement at 254 nm using vasicine as marker for standardization of the formulation. The method was found to be linear in the range of 4-12 ng/band. Isolation of vasicine from Adhatoda varica is also described.