J. Liq. Chromatogr. Relat. Technol. 31, 2673-2685 (2008). TLC of dehydroepiandrosterone on silica gel with chloroform - acetone 17:3 with chamber saturation for 30 min. Detection by dipping into 0.05 % aqueous solutions of visualizing agents (methylene violet, gentian violet, janus blue, methylene blue, malachite green, rhodamine B) and methanolic chloramine T/methanolic sulfuric acid solution. Quantitative determination by densitometry at 200 nm (before derivatization and for methylene violet), 657 nm (gentian violet), 487 nm (janus blue), 488 nm (malachite green), 580 nm (rhodamine B), and 361 nm (chloramine T). LOD was 0.29 µg/zone (without visualizing agent, with chloramine T and with rhodamine B), 4.19 µg/ zone with methylene violet, 1.10 µg/zone with gentian violet, 2.14 µg/zone with janus blue, and 4.19 µg/zone with malachite green, all with an application volume of 5 µL.

J. Planar Chromatogr. 23, 35-39 (2010). HPTLC of ß-carotene on silica gel (prewashed with methanol) with petroleum ether - hexane - acetone 2:3:1 in a saturated twin-trough chamber. Quantitative determination by absorbance measurement at 450 nm. Linearity was between 100 and 600 ng/band. LOD and LOQ were 0.11 and 0.37 ng/band, respectively. Average intra-day precision and inter-day-precision were 0.54 % and 0.50 %, respectively.

J. Planar Chromatogr. 23, 134-136 (2010). TLC of sertraline on silica gel (prewashed with methanol) with chloroform - ethyl acetate - triethylamine 25:15:1 in a twin-trough chamber previously saturated for 10 min at room temperature. Quantitative determination by absorbance measurement at 279 nm. The hRf for sertraline was 40. Intra-day precision and inter-day precision was 99.84 % RSD and 99.92 % RSD, respectively. A good linear relationship between response (peak area) and amount was obtained over the range 2.7-7.9 µg/band.

Abstract No. C-97, 61st IPC (2009). Chromatographic methods are reported for identification (TLC) and quantification (HPTLC) of withaferin-A in methanolic and chloroform extract of dried fruits of Withania coagulans. Chromatographic separation on silica gel with toluene - ethyl acetate - formic acid 5:5:1. The identification of withaferin-A in both chloroform and methanolic extracts was performed by comparison of hRf values and UV absorbance maxima (209 nm). Quantification was performed by absorbance measurement at 540 nm after spraying the developed plate with Liebermann-Burchard reagent. Methanolic extracts and chloroform extracts contained 3.67 mg/g and 2.10 mg/g of withaferin-A, respectively. No withaferin-A was found in hydroalcoholic extracts.

International Seminar on Herbal Drug Research, PN-024 (2009). HPTLC of catechins and epicatechin in leaves of tea (Camellia sinensis on silica gel with toluene - ethyl acetate - formic acid 7:5:1. Quantitative determination by absorbance measurement at 254 nm. The leaves were found to contain 10-24 % of total polyphenols.

Analytical Methods 2, 521-531 (2010). An HPTLC method for determination for paliperidone in formulation as well as for in vitro release studies has been developed. HPTLC on silica gel with methanol - ethyl acetate 4:1. The hRf value was 54. Quantification was performed by densitometric evaluation at 254 nm. The method was linear in the range of 100-600 ng/band. The method was suitable for estimation of the drug in mucoadhesive microemulsion formulations, as well as for solubility and diffusion studies.

Asian Journal of Chemistry 23(1), 469-470 (2011). Several herbal formulations were analyzed for gallic acid contents. Tablets were powdered, subjected to hydrolysis by refluxing with 10 % HCl, filtrated and extracted with chloroform. Acidic aqueous extracts were concentrated and the residue was taken up in methanol. TLC on silica gel with ethyl acetate - formic acid 85:11. Gallic acid was observed at an hRf value of 89. Densitometric quantification of gallic acid at 272 nm. The method was linear in the range of 100-3000 ng/band. The method was suitable for analysis of formulations without interference from excipients. Gallic acid contents of different tablet samples varied from 0.06-0.15 % w/w.

Microbiol. Res.166, 87-98 (2011). Two-dimensional TLC of phospholipids from Legionella bozemanae on chloroform - methanol - water 14:6:1 in the first dimension and chloroform - methanol - glacial acetic acid 13:5:2 in the second dimension. Lipids were detected by spraying with concentrated sulfuric acid or by exposure to iodine vapor. The following phospholipids were identified: phosphatidylcholine, phosphatidyl-N,N-dimethylethanolamine, phosphatidylethanolamine, phosphatidyl-N-monomethylethanolamine, phosphatidylglycerol and diphosphatidylglycerol.