2nd International Conference on New Development in Drug Discovery from Natural Product & Traditional Medicine PP82, 82 (2010). Eugenia jambolana pulp was dried in vacuum and enriched by chromatography on XAD 7HP ion-exchange resin, followed by Sephadex LH 20. HPTLC of both enriched extracts on silica gel with ethyl acetate – formic acid – acetic acid – water 100:11:11:26. Quantitative determination by absorbance measurement at 520 nm. The vaccum dried pulp and the enriched extracts 1 and 2 were found to contain 0.08 %, 17 % and 10 % of anthocyanins, respectively. Malvidin-3-laminariobioside was used as marker compound for quantitative analysis.

J. AOAC Int. 93, 754-764 (2010). The review describes analytical methods for drug substances, formulations, and clinical samples analyzed and validated by HPTLC during the period 1996-2009. Procedures, materials, and instrumentation for the different steps in the chromatographic procedure and validation of results are given; application to bulk drugs, formulations, stability studies, biological samples (e.g., urine and plasma), and hydrophobicity studies; and prospects for the future use of HPTLC for drug analysis are described. The sections cover the experimental procedures (sample preparation, stationary phases, mobile phases, application of standards and samples, chromatogram development, detection, documentation of chromatograms, densitometric quantitative analysis), determination of hydrophobicity, confirmation of zone identity, method validation, chiral separations, micropreparative layer chromatography, applications of HPTLC-densitometry, and future prospects for HPTLC in drug analysis. 155 references are reviewed.

J. Planar Chromatogr. 24, 105-107 (2011). TLC of twelve bisquaternary acetylcholinesterase reactivator HI-6-salts (sulfate, chloride, acetate, bromide, phosphate, mesylate, tartrate, iodide, malonate, salicylate, maleinate, and tosylate) on cellulose with acetone - acetic acid - water - toluene 5:2:2:1, butanol - acetic acid - water - toluene 1:1:1:1, isopropanol - acetic acid - water - toluene 5:2:2:1, and isopropanol - formic acid - water - toluene 6:2:2:1 in a twin-trough chamber. Detection under UV light at 254 nm and by spraying with Dragendorff’s reagent.

J. Planar Chromatogr. 24, 441-444 (2011). HPTLC of plant extracts and 17 polyphenolic compounds (apigenin, apigenin-7-glucoside, ellagic acid, hyperoside, isoquercitrin, kaempferol, kaempferol-3-glucoside, kaempferol-3-glucuronide, luteolin, luteolin-7-glucoside, methyl brevifolincarboxylate, myricetin, quercetin, quercetin-3-glucuronide, rutin, tiliroside, ellagic acid 3,3’-di-O-methyl ether 4-xylopyranoside) on silica gel (prewashed with methanol) with toluene - ethyl formate - formic acid 7:5:1 in an automatic developing chamber set with a twin-trough chamber at 22 °C and a relative humidity of 48 %. Detection under UV light at 254 and 366 nm, and at 366 nm after spraying with 1.0 % methanolic diphenylborinic acid 2-aminoethylester.

Acta Chromatographica 22 (4), 651-663 (2010). HPTLC of wedelolactone (WED) and asiaticoside (ASI) in Eclipta alba and Centella asiatica Linn., respectively, on silica gel with toluene - acetone - methanol - formic acid 60:40:40:1. The hRf value was 26 and 75 for ASI and WED, respectively. Detection by spraying with 10 % methanolic sulphuric acid. Quantitative evaluation by absorbance measurement at 317 nm for WED and at 530 nm after derivatization for ASI. The linearity was in the range of 50-250 ng/band for WED and 150-550 ng/band for ASI with r = 0.999 for WED and 0.9989 for ASI. The recovery of WED was 99.3 % and of ASI 99.5 %.

J. Planar Chromatogr. 23, 315-319 (2010). HPTLC of polyphenols (extracted from Quercus robur) and quercetin, chlorogenic acid, gallic acid, and rutin as standards on silica gel with ethyl acetate - water - formic acid 87:3:10 in an unsaturated twin-trough chamber. Detection by spraying with 1 % 2-aminoethyl diphenylborinate (natural products reagent) followed by 2 % polyethylene glycol 4000 solution as well as by spraying with 2 % phosphomolybdic acid reagent followed by heating at 120 °C for 5 min. Evaluation by densitometry in absorption mode at 700 nm.

J. Planar Chromatogr. 24, 130-135 (2011). TLC of Juniperus essential oils (containing terpenoids, monoterpenes, sesquiterpenes and alcohols) with guaiazulene and cineole as standards on silica gel with ethyl acetate - toluene 1:19. Detection by spraying with anisaldehyde reagent followed by heating for 5 min at 100 °C and examination under daylight. The hRf values were 42 and 89 for cineole and guaiazulene, respectively.

J. Planar Chromatogr. 25, 504-508 (2012). Physical properties of polar and non-polar solvents under electric current pulse were studied. In addition, solvents were classified according to their behavior in a pulsating electric field with applications in planar dielectrochromatography.