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 %.

from the Western Himalayas. J. Planar Chromatogr. 28, 391-394 (2015). HPTLC of precocene I in Ageratum conyzoides L. on silica gel with hexane - chloroform 3:2. Quantitative determination by absorbance measurement at 300 nm. The hRF value for precocene I was 25. The calibration range was 400-1200 ng/zone. LOD and LOQ were 1040 and 3160 ng/mL. The intermediate precision was below 6.5 % (n=3). Recovery was in the range of 98-101 %.

J. Planar Chromatogr. 29, 405-409 (2016). 2D-HPTLC of chlorogenic acid (1), rutin (2), caffeic acid (3), apigenin (4) and naringin (5) in ten samples of the selected Cirsium species on RP-18 with 2-butanone ‒ toluene ‒ acetic acid 9:10:1 used in the first direction and methanol ‒ water ‒ formic acid 4:5:1 used in the second direction. Detection by spraying with natural products reagent (1 g diphenylborinic acid 2-aminoethylester in 100 mL methanol) followed by PEG reagent (5 g PEG 4000 in 100 mL methanol). The hRF values were 71 for (1), 39 for (2), 57 for (3), 7 for (4) and 50 for (5) in the first direction and 36 for (1), 7 for (2), 82 for (3), 86 for (4) and 6 for (5) in the second direction.

tincture using thin-layer chromatography–direct_x000D_ bioautography and liquid chromatography–tandem mass spectrometry techniques. J. Planar Chromatogr. 30, 357-362 (2017). HPTLC bioautography of Salvia officinalis on silica gel with chloroform ‒ diethyl ether ‒ methanol 30:10:1. Direct bioautography by dipping into bacterial cell suspension for 10 s, followed by incubation at 37 °C for 5 h. After incubation, plates were dipped in the aqueous solution of MTT (0.05 g 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide in 90 mL) for 5 s and further incubated at 37 °C for 2 h. The antibacterial components of S. officinalis L. extract, active against seven bacterial strains were identified by combining the method with LC–MS/MS analysis of zones interested.

J. Chromatogr. Sci. 56, 518-523 (2018). Presentation of a validated method for the quantitation of dihydrokaempferol-4′-O-glucopyranoside. This flavanonol glucoside is a marker compound in the flower of Alcea rosea L. with significant antioxidant and anticancer activity against the HepG-2 cell line. HPTLC on silica gel with ethyl acetate – methanol – water – acetic acid 600:100:80:3 over 70 mm with chamber saturation for 30 min. Quantitative determination by absorbance measurement at 295 nm. The amount of dihydrokaempferol-4′-O-glucopyranoside in the flowers of A. rosea was 0.733 g/100 g and 0.928 g/100 g after maceration and sonication for 15 min, respectively. Linearity was in the concentration range of 0.9-3.6 µg/zone. The %RSD of the intra-day and inter-day precision was 0.2–1.5 % and 0.5–1.7 %, respectively. The LOD and LOQ were 312 ng/zone and 947 ng/zone, respectively.

Phytochemistry. 24, 1495- 1498 (1985). Two-dimensional TLC of extracts of phyllocladus species on cellulose with 1) t-butanol - acetic acid - water 3:1:1 and 2) acetic acid - water 6:94. Detection with vanillin-HCl reagent. Catechin, epicatechin and phylloflavan, a new flavanoid compound readily resolved.

Phytochemistry 25, 1719-1721 (1986).TLC of flavonoid sulfates on cellulose with butanol - acetic acid - water 3:1:1 or on polyamide with methanol - water -29 % NH3 10:9:1. Detection with 2-aminoethyldiphenylborinate (0.1 % in methanol). TLC of the hydrolysis products on polyamide with benzene - MEK - methanol 3:1:1. Also ion pairing HPLC. Specific analytical procedure for the detection of flavonoid sulfates in plant extracts.

Acta Pharm. Hungarica 57, 193-198 (1987). HPTLC of rutin, vitexin-4'- rhamnoside, hyperoside, vitexin and apigenin-7-glucoside on silica with ethyl acetate - formic acid - acetic acid - water 100:11:11:28 for glycosides, with toluene - ethyl acetate - acetic acid - water 30:50:16:4 for aglycones. Detection under UV 254 and 366 nm and spraying with 1% AlCl3 methanolic solution. Densitometry by absorbance at 400 nm.