J. Planar Chromatogr. 27, 29-32 (2014). HPTLC of rhein in the pulp of Cassia fistula on silica gel with ethyl acetate - methanol - water 100:17:10. Quantitative determination (1) by TLC image analysis using a flatbet scanner and (2) by absorbance measurement at 435 nm. The hRF value for rhein was 49. Linearity was in the range of 400-1200 ng/zone for (1) and 29-230 ng/zone for (2). The intermediate/interday/intra-day precisions were below 3 % (n=3). The LOD and LOQ for rhein were 85 and 257 ng/zone for (1) and 3 and 11 ng/zone for (2). Mean recovery was 102.3 % for (1) and 101.2 % for (2).

Food Chem. 168, 520-528 (2015). HPTLC of lipids and fatty acids in mussels (Mytilus sp.) on silica gel with methyl acetate - isopropanol - chloroform - methanol - 0.25 % potassium chloride 25:25:25:10:9 as the polar solvent and further developed with hexane - diethyl ether - glacial acetic acid 40:10:1. Detection by spraying with a copper acetate reagent (10 % cupric sulfate in 8 % aqueous phosphoric acid). Quantitative determination by absorbance measurement at 535 nm.

J. Liq. Chromatogr. Relat. Technol. 37, 1114-1132 (2014). HPTLC of rosuvastatin on silica gel with chloroform - n-hexane - methanol - glacial acetic acid 80:100:40:15:1. Quantitative determination by absorbance measurement at 295 nm. The hRf value for rosuvastatin was 9. Degradation products (DPs) were characterized by ESI-MS. For acidic hydrolysis, 4 major DPs with hRF values of 16, 27, 74 and 77 were obtained. For alkaline hydrolysis, one major DP of hRF 73 was detected. For thermal hydrolysis two major DPs with hRF 74 and 77 were detected. For exposure to hydrogen peroxide, 5 major DPs with hRF 15, 25, 30, 71 and 77 were obtained. For photolytic hydrolysis, 2 major DPs with hRF 70 and 78 were detected. Linearity was in the range of 500-20000 ng/zone. The intermediate/interday/intra-day precisions were below 2 % (n=3). The LOD and LOQ were 170 and 500 ng/zone. Average recovery was 99.9 %.

J. Planar Chromatogr. 27, 267-273 (2014). HPTLC of kaempferol (1), rutin (2), and quercetin (3) in marketed formulations containing_x000D_ Phyllanthus niruri (Bhuiamla) and Emblica officinalis (Amla) on silica gel with chloroform - methanol - formic acid 82:15:10. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) to (3) were 69, 53 and 12. Linearity was in the range of 21-840 ng/zone for (1), 56-1008 ng/zone for (2) and 60-1800 ng/zone for (3), respectively. The intermediate/interday/intra-day precisions were below 1 % (n=3). The LOD and LOQ were 21 and 63 ng/zone for (1), 56 and 168 ng/zone for (2) and 300 and 600 ng/zone for (3), respectively. Recoveries for (1) to (3) were obtained in the range of 81.8-119.0 %.

Chinese J. of Forestry Science 49 (10), 127-134 (2013). Flavonoids in bamboo leaves have free radical scavenging, antioxidant, anti-aging, antibacterial, and anti-inflammatory effects and are used as a component in TCM for regulating blood fat and preventing cardiovascular and cerebrovascular diseases. Bamboo-leaf flavonoids are also used in cosmetics and as feed additive. In order to choose the best bamboo species for extraction of flavonoids and to set up a quality control method, the flavonoids in eleven samples of bamboo leaves of three genera collected from Yunnan, Fujian, Sichuan, Jiangsu and Jiangxi provinces are studied by HPTLC. HPTLC-AMD of sample extracts and the standards isoorientin, orientin, isovitexin, vitexin and tricin on silica gel, cleaned with methanol and methylene chloride and dried at 105 °C, with methanol – ethyl acetate – methylene – formic acid 4:7:9:2 to 50 mm in the first step, with acetone – methanol - ethyl acetate – methylene chloride – formic acid 1:2:7:10:2 to 75 mm in the second step, and with acetone - methanol - ethyl acetate - methylene chloride – formic acid 2:1:6:11:2 to 90 mm in the third step. Detection under UV 366 nm after spraying with 1 % aluminum trichloride in ethanol. Quantification of the flavonoids by densitometry at UV 366 nm via peak area. The quantitative method for different flavonoids was validated by investigation of the linearity (90-1750 ng/zone), the precision (%RSD=1.0-2.0 %, n=3 intra-day; %RSD=0.9-2.0 %, n=3 inter-day), and the repeatability (%RSD=0.9-1.9 %, n=9). The LODs were 25-40 ng/zone, and the recoveries were 81.3-106.9 % (n=3).

J. Planar Chromatogr. 27, 472-476 (2014). HPTLC of (1) genistein and (2) vitexin in seeds of Vigna mungo on silica gel with toluene – ethyl acetate – methanol – acetic acid – formic acid 6:14:2:1:1 after saturation with mobile phase for 25 min. Quantitative determination by absorbance measurement at 254 nm. The hRF values of (1) and (2) were 81 and 31, respectively. Linearities were in the range of 500-2500 ng/zone for (1) and (2). The intermediate precisions were below 8 % (n=6) for (1) and (2). The LOD and LOQ were 14 and 42 ng for (1) and 52 and 159 ng for (2), respectively. Recoveries for (1) and (2) were in the range of 96.1-97.1 and 95.7-97.6 %.

J. Planar Chromatogr. 28, 67-73 (2015). HPTLC of (1) rifampicin, (2) isoniazid and (3) piperine on silica gel with toluene – methanol – chloroform 7:3:3. Quantitative determination by absorbance measurement at 300 nm. The hRF values of (1) to (3) were 51, 24 and 81, respectively. Linearities were between 100 and 700 ng/zone for (1) and (2) and between 20 and 90 ng/zone for (3). The intermediate intra-day and inter-day precisions for (1) to (3) were below 2 % (n=6). The LOD and LOQ were 12 and 33 ng/zone for (1), 20 and 53 ng/zone for (2) and 5 and 10 ng/zone for (3). Recoveries for (1) to (3) were in the range of 99-101 %.

J. Liq. Chrom. Rel. Tech. 38, 271-282 (2015). HPTLC of (1) terazosin, (2) doxazosin, (3) prazosin, and (4) alfuzosin in plasma on silica gel with acetonitrile - phosphate buffer 3:7 at pH 3. Quantitative determination by absorbance measurement at 332 nm. The hRF values of (1) to (4) were 52, 47, 53 and 41, respectively. Linearities were between 10 and 100 ng/zone for (1) and (2), between 15 and 75 ng/zone for (3) and between 5 and 100 ng/zone for (4). The LOD and LOQ were 4 and 9 ng/zone for (1), 5 and 10 ng/zone for (2), 7 and 14 ng/zone for (3) and 4 and 5 ng/zone for (4), respectively. The intermediate intra-day and inter-day precisions were below 2.6 % (n=6). Mean recoveries were found in the range of 94.2-99.9 %.