J. Chinese Modern Med. & Pharm. 18 (1), 40-42 (2011). TLC on silica gel with petroleum ether (60-90 ºC) – ethyl acetate 1:1. Detection under UV 254 nm. Identification by comparison of the fingerprint of the main component, Rehmanniae Radix.

J. Planar Chromatogr. 24, 400-405 (2011). TLC of plant extracts and kaempferol, quercetin, and rutin as standards on silica gel with ethyl acetate - formic acid - acetic acid - water 100:11:11:27 with chamber saturation for 30 min. Detection by spraying with 1 % methanolic diphenylborinic acid 2-aminoethylester followed by 5 % ethanolic polyethylene glycol 4000. Evaluation under UV 366 nm. Detection of the antioxidant activity with DPPH radical reagent. Videodensitometric analysis of the derivatized TLC plates. The hRf value was 24 for rutin, 98 for quercetin and 100 for kaempferol.

and Gentianella acuta by thin-layer chromatography) (Chinese). J. of Inner Mongolia Univ. for Nationalities (Natural Sci. Edit.) 26(1), 71-72 (2011). TLC of the extracts of the title medicinal herbs on silica gel with 1) chloroform - methanol - water - formic acid 28:2:2:1, detection by spraying with 10 % sulfuric acid in ethanol and heating at 105 °C until the zones were detected; 2) chloroform - methanol - ammonia 40:10:1, detection by spraying with iodine solution. Identification by comparison of the fingerprint with the main components gentianine, isoorientin, flavone, isobellidifolin, swerchirin, and 1,5,8-trihydroxy-3,4-dimethoxyxanthone.

J. Planar Chromatogr. 24, 116-120 (2011). HPTLC of rosin, rosarin, and rosavin in the roots of Rhodiola rosea L. and Rhodiola sachalinensis Borissova on silica gel, prewashed with methanol, with chloroform - methanol - water 130:70:21 in a twin-trough chamber lined with filter paper and saturated for 20 min, at 21-24 °C and 40-45 % relative humidity. Quantitative determination by densitometry at 250 nm. The calibrations were linear in the range of 100-500 ng/band with correlation coefficients of 0.9999, 0.9992, and 0.9992 for rosin, rosarin, and rosavin, respectively. Recovery of the three compounds was between 97 and 101 %. The LOD and LOQ were 30 and 100 ng/band, respectively, for all three compounds. The hRf values for rosin, rosarin, and rosavin were 58, 45, and 42, respectively. Intra-day variation, as %RSD, was 2.7 % for rosin, 1.7 % for rosarin, and 2.8 % for rosavin, with standard errors of 0.3 %, 0.2 %, and 0.3 %, respectively. Inter-day variation, as % RSD, was 4.8 % for rosin, 4.2 % for rosarin, and 3.9 % for rosavin, with standard errors of 0.5 %, 0.5 %, and 0.4 %, respectively.

J. Liq. Chromatogr. Relat. Technol. 32, 2893-2905 (2009). HPTLC of albiflorin, paeoniflorin, (beta)-catechin, benzoyloxypaeoniflorin, benzoylpaeoniflorin, beta-sitosterol in the roots of Radix paeoniae Rubra (1) and Radix Paeoniae Alba (2) on silica gel with chloroform - ethyl acetate - methanol - formic acid 30:5:10:1 for high polarity components and toluene - ethyl acetate - methanol - formic acid 20:4:2:1 for lipophilic components. Detection by spraying with vanillin - sulphuric acid - ethanol 1:5:95, followed by heating at 105 ºC for 10 min. Qualitative determination by densitometry at 366 nm. The HPTLC fingerprints allowed differentiation between the roots of (1) and (2).

J. Planar Chromatogr. 24, 507-512 (2011). HPTLC of flavonoids (quercetin and kaempferol) and biflavonoids (sciadopitysin, ginkgetin, and bilobetin) in aqueous methanolic extracts of Ginkgo biloba on RP-18 by double development with 1) acetonitrile - water - methanol - formic acid 20:20:1:0.005 and 2) acetonitrile - water - methanol - formic acid 20:17:1:0.005. Quantitative determination by densitometry in absorption mode at 254 nm. LOD and LOQ were in the range of 0.12-0.37 and 0.60-1.85 µg/zone, respectively. Linearity was found over the concentration range of 0.5-4.0 µg/zone for quercetin, kaempferol, sciadopitysin, ginkgetin, and bilobetin with correlation coefficients r = 0.9990, 0.9922, 0.9939, 0.9974, and 0.9706, respectively. Average recoveries were in the range of 97.7-100.4 %.

J. Liq. Chromatogr. Relat. Technol. 34, 1925-1937 (2011). HPTLC of p-hydroxy benzoic acid (1), chrysoplenol-D (2), p-methoxy benzoic acid (3) and casticin (4) in the aerial parts of Vitex trifolia on silica gel with chloroform - methanol 24:1 + 1 drop formic acid. Quantitative determination by absorbance measurement at 254 nm. The hRf values of compounds (1) - (4) were 25, 31, 63 and 87, respectively. LOD and LOQ were found to be 18-58 ng/zone for (1), 39-132 ng/zone for (2),15-52 ng/zone for (3) and 33-111 ng/zone for (4). Repeatability and reproducibility (%RSD) for (1)-(4) were found in the range of 0.8-1.2 % and 1.2-1.3 %, respectively. Recoveries were obtained in the range of 94.0-101.1 %, 97.8-102.0 %, 95.1-100.1 %, and 97.6-100.3 % for compounds (1) - (4), respectively.

J. Planar Chromatogr. 25, 534-541 (2012). TLC of anthocyanins and anthocyanidins in berry fruits on cellulose layers with hydrochloric acid - glacial acetic acid - water 10:1:3. Quantitative determination by absorbance measurement at 520 nm. The hRf values obtained for pelargonidin and cyanidin were 78 and 58, respectively. The TLC method was complementary to an HPLC method and allowed for identification of the major anthocyanidins characteristic for each berry fruit.