Anal. Chim. Acta 690 (2), 148-161 (2011). Chromatographic fingerprinting has been generally accepted as analytical method for the quality control of herbal medicines. This review describes the evolution of the regulations and guidelines on the quality control of herbal medicines, and reviews the established analytical techniques in TLC, HPLC, UHPLC, hydrophilic interaction chromatography, and GC. Emphasis is put on the most recent developments, such as miniaturized techniques, new stationary phases, analysis at high temperatures and multi-dimensional chromatography. The new chemometric data handling techniques are discussed.

Acta Chromatographica 22 (3), 481-489 (2010). HPTLC on silica gel with toluene – ethyl acetate – methanol – formic acid 8:10:5:2. The hRf values were 22, 19, and 81 for sennosides A and B and kaempferol, respectively. Quantification by densitometry at 270 nm. The recovery of sennosides A and B and kaempferol from Cassia fistula extract were 98.0, 98.7, and 99.1 %, respectively. The linearity was in the range of 100–400 ng/band. Instrument precision was in the range of 1.03-1.33 % and method precision in the range of 1.3-1.8 %.

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. 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.

J. Planar Chromatogr. 24, 373-375 (2011). HPTLC of red clover capsule extracts and formononetin, biochanin A, daidzein, glycitein, and genistein on silica gel, prewashed with methanol, with dichloromethane - glacial acetic acid - ethyl acetate 12:2:1 in a horizontal chamber saturated for 15 min. Quantitative determination by densitometry at 260 nm. The hRf value was 29, 34, 41, 48, and 59 for daidzein, glycitein, genistein, formononetin, and biochanin A, respectively. The two major isoflavones are formononetin and biochanin A. The limit of detection and quantification was 14 and 47 ng/band for formononetin and 12 and 40 ng per band for biochanin A, respectively. The recovery was 93.3-100.7 % for formononetin and 102.0-109.4 % for biochanin A.

J. Planar Chromatogr. 24, 497-502 (2011). HPTLC of isoswertisin-5-O-beta-D-glucoside (1), swertiamarin (2), and swertisin (3) as biomarkers on silica gel with ethyl acetate - methanol - water 16:2:1 in a twin-trough chamber with saturation for 30 min. Quantitative determination by absorbance measurement at 287 nm. Linearity was between 25-75 µg/mL for (1), 200-600 µg/mL for (2), and 100-300 µg/mL for (3). The relative standard deviation for instrumental precision, intra-assay precision, and intermediate precision was below 2 %. The average recovery was 99.9 % for (1), 99.6 % for (2), and 99.1 % for (3). The hRf values were 32 for (1), 41 for (2), and 52 for (3). The limit of detection was 570 ng, 740 ng, and 300 ng for (1), (2), and (3), respectively.

J. of Chromatogr. A 1218 (33), 5693-5704 (2011) A micro-TLC platform for the fast analysis of low-molecular mass compounds from spirulina samples was developed. The target compounds were extracted with methanol, acetone or tetrahydrofuran. HPTLC on RP-18W with acetone - n-hexane 3:7 in an unsaturated chamber using a temperature controlled micro-planar chromatographic device based on a horizontal chamber. Detection under visible light before and after exposure to iodine vapor. Pictures of the chromatograms were acquired with an office scanner and digitalized. The quantitative data was analyzed using cluster analysis and principal components analysis. With this method it was possible to distinguish genuine spirulina and non-spirulina samples as well as fresh and expired commercial products.

Indian drugs 48 (02), 43-47 (2011). TLC of curcumin and 3-acetyl-11-keto-beta-boswellic acid on silica gel with chloroform - methanol 37:3 for curcumin and n-hexane - ethyl acetate 1:1 for boswellic acid derivatives. The hRf value of 3-acetyl-11-keto-beta-boswellic acid was 24 and of curcumin 59. Densitometric evaluation at 430 nm for curcumin and 254 nm for the acid. The method was linear in the range of 100-500 ng/band for curcumin and 1500-4000 ng/band for 3-acetyl-11-keto-beta-boswellic acid.