J. Tech. & Sci. of Ningxia Agr. & Forest, 5, 38-39 (2010). For liquorice TLC on silica gel with ethyl acetate - glacial acetic acid - formic acid - water 15:1:1:2, detection by spraying with 10 % sulfuric acid in ethanol and heating at 105 ºC. For Rhizoma zingiberis TLC on silica gel with cyclohexane - diethyl ether 1:1, detection by spraying with 10% vanillin in sulfuric acid and heating at 105 ºC, followed by evaluation in daylight.

International Journal of Pharma and Bio Sciences 1(1), 2-4 (2010). TLC of methanol 50 % extracts of cut dried flowers of Calendula officinalis on silica gel with chloroform – methanol 19:1. The hRf value of quercetin was 43. Quantitative determination by densitometry at 366 nm. The method was linear in the range of 1-5 µg/band. The identity of quercetin in the sample was confirmed by comparing hRf values and UV spectra of sample and standard.

Acta Chromatographica 22 (3), 491-497 (2010). HPTLC of lupeol (methanolic Soxhlet extract from the bark of Mimosoups elengi) on silica gel with toluene – ethyl acetate – formic acid 12:2:1. The hRf value of lupeol was 64. Evaluation by densitometry at 220 nm. The linearity was in the range of 1–4 µg/band. The precision was 1.06 and 1.03 %RSD, respectively. Recovery was 97.3 %.

Chinese J. Ethnomed. Ethnopharm. (23), 61-64 (2010). Optimization of the sample preparation procedure for Herba Saururi chinensis 1) by ultrasonication with methanol for 60 min; 2) by ultrasonication with methanol for 20 min and filtration through neutral alumina column with methanol; 3) by reflux extraction with 80 % methanol for 60 min and extraction with diethyl ether; 4) by ultrasonication with ethanol for 60 min; 5) by ultrasonication with methanol - 25 % hydrochloric acid 4:1 for 60 min and extraction with ethyl acetate. Procedure 5) was best suited. TLC on silica gel 1) with petroleum ether (60-90 °C) – acetone 5:2, and detection by spraying with 10 % sulfuric acid in ethanol and heating at 105 ºC until the zones appear; 2) with toluene – ethyl acetate – formic acid 5:2:1, and detection by spraying with 1 % AlCl3 in ethanol and evaluation under UV 366 nm; 3) with n-hexane – ethyl acetate – formic acid 70:50:8, and detection by spraying with 1 % AlCl3 in ethanol, heating at 105 ºC and evaluation under daylight or under UV 366 nm; 4) with toluene – ethyl acetate – formic acid 5:4:1 with chamber saturation with hydrochloric acid vapor, detection under daylight or UV 366 nm.

J. Planar Chromatogr. 24, 394-399 (2011). TLC of leave extracts and six flavonoids as markers (vitexin, isovitexin, orientin, isoorientin, quercetin, and tricin) on silica gel, prewashed with methanol and methylene chloride, with methanol - ethyl acetate - acetone - methylene chloride in different ratios using automated multiple development. The developed plate was dried in air for 2 h and sprayed with 1 % aluminum trichloride in ethanol. Then the plate was left for 2 h for derivatization in a glass drying chamber. Quantitative determination by densitometry at 366 nm. The hRf values of the six marker flavonoids were 22, 31, 38, 45, 57, and 88, respectively. Linearity was between 175 and 1750 ng/band. Instrument precision (n = 10) was between 0.2-0.9 %. The repeatability for standards and samples (n = 9), was 0.7 and 0.5, 0.8 and 0.5, 0.8 and 0.5, 0.8 and 0.4, 1.3 and 0.7, 1.1 and 0.3 % for isoorientin, orientin, isovitexin, vitexin, quercetin, and tricin, respectively. The limits of detection were 35, 40, 35, 50, 80, and 20 ng/zone for isoorientin, orientin, isovitexin, vitexin, quercetin, and tricin, respectively. The intra-day and inter-day precision was between 0.1-2.9 % and 0.3-2.4 % for all six marker flavonoids.

J. Planar Chromatogr. 23, 348-352 (2010). TLC of methoxylated flavones G1, G2, G3, G4 (3’,4’,5’-trimethoxyflavone), and G5 on alumina with n-hexane - ethyl acetate 7:3 at ambient temperature with chamber saturation. Detection by visual inspection at 365 nm. The hRf values of G1 (monomethoxyflavone), G2 (monomethoxyflavone), G3, G4 (trimethoxyflavone), and G5 (dimethoxyflavone) were 42, 30, 22, 17, and 12, respectively.

J. Planar Chromatogr. 24, 264-267 (2011). TLC of crebanine on silica gel with toluene - ethyl acetate - methanol 14:3:3 in a twin-trough chamber saturated for 1 h at 25 +/- 2 °C. Detection under UV light at 254 nm. Quantitative determination by densitometry in absorbance mode at 286 nm. The method precision (%RSD, n = 3) and the instrument precision (%RSD, n = 6) were 0.9 and 0.5 %, respectively. The repeatability (%RSD, n = 5) was 0.8; the accuracy as average recovery was 100.1 %. The limit of detection and quantification was 10 and 15 ng/zone, respectively. Linearity was between 100-500 ng/zone. The hRf value was 54.

J. Planar Chromatogr. 24, 539-540 (2011). HPTLC of 13 wood extracts and taxifolin, quercetin, chlorogenic acid, fisetin, apigenin, kaempferol, and 3-methoxyflavon as standards on silica gel with toluene - ethyl acetate - formic acid 6:3:1 in an unsaturated twin-trough chamber. Detection by spraying with natural products reagent, then with polyethylene glycol 400 solution. Evaluation under UV 366 nm.