J. Liq. Chromatogr. Relat. Technol. 32, 1289-1298 (2009). HPTLC of phosphatidylcholine (1), phosphatidylethanolamine (2), sphingomyelin (3), sulfatides (4), and cerebrosides (5) in tissue samples of the lizard Uta stansburiana on silica gel with chloroform - methanol - water 65:25:4. Detection by spraying with 10 % cupric sulfate in 8 % phosphoric acid, followed by heating at 140 ºC for 30 min. Quantitative determination by absorbance measurement at 370 nm. The hRf values of (1)-(5) were 40, 56, 39, 51 and 71, respectively.

J. Liq. Chromatogr. Relat. Technol. 32, 3049-3055 (2009). HPTLC of cinoxacin (1), pipemidic acid (2), ofloxacin (3), and pefloxacin (4) on silica gel with buffer solution (pH 5.5) - methanol 4:1 and acetonitrile - water - acetic acid, 3:20:2. Detection by dipping into various visualization agents. The detection limits for (1) to (4) were 0.1, 0.1, 0.5, and 0.75 µg/zone, respectively. Best detection conditions for (1) and (2) were obtained by dipping in Janus blue and immediate evaluation, and for (3) and (4) by dipping in Cresol red followed by heating at 120 ºC for 10 min for (3) and (4).

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.

Ham. Ex D. Don, Myricaceae. J. Planar Chromatogr. 23, 326-331 (2010). HPTLC of myrecitin and stem bark extracts on silica gel with toluene - ethyl acetate - formic acid - methanol 15:15:3:2. Quantitative determination by absorbance measurement at 268 nm. Linearity was between 0.4-2.0 µg/band. The limits of detection and quantitation were 93 ng and 284 ng/zone. The intra-day and inter-day precision of the method was in the range of 0.14-0.55 %. The recovery of myrecitin at three concentrations was in the range of 98.9-100.1 % and the average recovery was 99.3 %.

J. Planar Chromatogr. 24, 406-411 (2011). HPTLC of plant extracts and vasicine on silica gel with ethyl acetate - methanol - ammonia (17.3 % ammonia) 40:10:1 in a twin-trough chamber saturated for 15 min. Quantitative determination by densitometry at 298 nm. The hRf value of vasicine was 47. The limit of detection and the limit of quantification was 40 and 100 ng/zone, respectively. The average intra-day and inter-day precision was 0.7 and 2.2 %, respectively. Linearity was between 100-1300 ng/zone with a correlation coefficient of 0.999 and a %RSD of 2.3 %. Average recovery was 98.9 %.

extracts on polar-bonded stationary phases. J. of Chromatogr. A 1218 (19), 2812-2819 (2011). Two-dimensional TLC of phenolic compounds (extracted from Polygonum hydropiper L. and Polygonum cuspidatum L.) on cyano phase with non-aqueous solvents in the first direction and aqueous solvents in the second direction. For the separation of standards the optimal chromatographic systems was determined based on the retention data collected in one-dimensional TLC experiments by plotting graphs of Rf vs. Rf dependencies.

Der Pharmacia Letter 2(4), 440-446 (2010). TLC of glibenclamide on silica gel with toluene - ethyl acetate - methanol 16:1:2. The hRf value was 45. Quantitative determination by densitometry in absorbance mode at 229 nm. The method was linear in the range of 40-200 ng/band. The recovery was 99.8 %.

J. Liq. Chromatogr. Relat. Technol. 34, 920-927 (2011). TLC of flumequine in milk on silica gel with dichloromethane - methanol - 2-propanol - 25 % aqueous ammonia 3:3:5:2. Bioautography by dipping into an Escherichia coli bacteria suspension for 5 h at 37 ºC. After incubation, the plates were sprayed with 0.2 % MTT ([3-(4,5-dimethyldiazol-2-yl)-2,5 diphenyltetrazolium bromide] aqueous solution and incubated for about 30 min at 37 ºC. The new procedure gave better recoveries of flumequine residues from milk compared with the previous method.