Asian Journal of Chemistry 22(10), 8117-8120 (2010). HPTLC of beta-sitosterol in leaves, roots and seed oil of 3 species of Jatropha. Chromatographic separation on silica gel with toluene - methanol 9:1. The hRf value of beta-sitosterol was 54. Derivatization with anisaldehyde-sulfuric acid reagent, followed by heating at 120 °C. After derivatzation densitometric evaluation at 525 nm. The method was linear in the range of 100-500 ng/band. The proposed method was used for the estimation of beta-sitosterol in extracts of different species of plants. The presence of beta-sitosterol in samples was confirmed by multi-wave length scanning.

Acta Chromatographica 22 (2), 227-236 (2010), DOI:10.1556/AChrom.22.2010.2.6. TLC of piperine, the bioactive constituent of black pepper (Piper nigrum), on silica gel with dichloromethane – ethyl acetate 9:1 at 30 °C in a twin-trough chamber saturated for 30 min. Detection under UV light at 254 nm and documentation with a digital camera. Based on the image a density profile plot was established by Scion Image software, which allowed to calculate the concentration of piperine by comparison of the peak areas of samples and piperine standards. The linearity was in the range of 24-84 ng/zone (r2=0.9927). The limits of detection and quantitation were 0.35 and 1.05 ng/zone, respectively. Precision (repeatability, n=6) and intermediate precision (2 days, n=12) both are below 2.6 %RSD. Recovery is between 96.7-101.4 %.

J.of Jiangxi Univ. of TCM 22 (5), 55-57 (2010). TLC of Shujinhuoxue pills: 1) for Angelica sinensis, on silica gel with cyclohexane – ethyl acetate 12:1, detection under UV 365 nm; 2) for Rheum officinale, on silica gel with petroleum ether (30-60 ºC) – ethyl formate – formic acid 15:5:1, detection by exposure to ammonia vapors; 3) for Radix Rehmanniae praeparata, on silica gel with petroleum ether (60-90 ºC) – ethyl acetate 1:1, detection under UV 254 nm; 4) for Gardenia jasminoides, on silica gel with ethyl acetate – acetone – formic acid – water 5:5:1:1, detection by spraying with 10 % sulfuric acid in ethanol and heating at 110 ºC until the zones were visualized; 5) for Lignum Sappan, on polyamide phase with 36 % acetic acid, detection by spraying with 5 % AlCl3 in ethanol and heating mildly until the spots were visualized.

J. of China Pharm. 19 (23), 24-25 (2010). TLC of the extracts of traditional Chinese formulations and some health-care foods on silica gel with dichloromethane - acetone 4:1. Detection under UV 254 nm. This TLC method was better than the previously used one with the mobile phase dichloromethane - diethyl ether - methanol - water 385:60:15:2 and detection reagent 2 % tetrazolium solution - 2N NaOH - methanol 3:10:5. Identification of dexamethasone, prednisone, prednisolone acetate, prednisone acetate, cortisone acetate, hydrocortisone, betamethasone, hydrocortisone acetate, dexamethasone acetate, fluocinolone acetonide acetate by comparison with the standards. The improved procedure proved to be simple, fast, robust and suitable for quick screening of 10 glucocorticoids illegally added to some traditional Chinese formulations and health-care foods.

PHCOG J. 2(11), 381-385 (2010). TLC of Tylophora indica leaves, extracted with petroleum ether, chloroform and methanol, on silica gel with 1) n-hexane - ethyl acetate 2:3 for the petroleum ether extract, 2) chloroform - ethyl acetate - methanol 18:1:1 for the chloroform extract, and 3) chloroform - toluene - ethyl acetate 18:1:1 for the methanolic extract. Evaluation under UV 254 nm and 366 nm. 12 prominent bands were observed in all chromatographic fingerprints. The method is suitable for identification and authentication of the plant material.

Food Chemistry 131, 1517-1522 (2012). HPTLC fingerprinting of 6-gingerol (1), 8-gingerol (2), 10-gingerol (3) and 6-shogaol (4), in the rhizome of Jamaican ginger (Zingiber officinale Roscoe) on silica gel with hexane - ethyl acetate - formic acid 11:8:1. Detection by spraying with either 5 % ammonium molybdate in 10 % sulfuric acid, or 0.5 mL p-anisaldehyde in 50 mL glacial acetic acid and 1 mL 97 % sulfuric acid. Quantitative determination by densitometry at 366 nm. The hRf values of (1) - (4) were 46, 49, 52 and 64, respectively. This method of chemical fingerprinting is a suitable analysis for rapid determination of the authenticity of the ginger product as a chemical composite.

J. of China Pharm. 20 (9), 16-17 (2011). TLC of the extracts of Biyan syrup 1) for Herba Ephedrae, on silica gel with chloroform - methanol - ammonia 40:10:1, detection by spraying with ninhydrin reagent and heating at 105 ºC; 2) for Flos Magnoliae, on silica gel with chloroform - diethyl ether 5:1, detection by spraying with 10 % sulfuric acid in ethanol and heating at 105 ºC; 3) for Radix Astragali, on silica gel with ethyl acetate - butanone - formic acid - water 5:3:1:1, detection by spraying with 5 % iron(III) chloride in ethanol; 4) for Angelica dahurica (Fisch.) Benth. et Hook, on silica gel with toluene - petroleum ether (60-90 ºC) - ethyl acetate 6:3:1, detection under UV 366 nm.

Journal of Pharmacy Research 4(4), 1197-1198 (2011) Vitamin C contents were estimated in fruit and fruit pulp. HPTLC of vitamin C from methanolic extracts of Pithecellobium dulce pods on silica gel with ethanol - water 2:1. Densitometric quantification at 254 nm. The method was linear in the range of 100-600 ng/band. The method could be employed for quality control of formulation containing the plant as one of the ingredient.