J. Planar Chromatogr. 24, 206-210 (2011). HPTLC of free sterols, free fatty acids, triacylglycerols, methyl esters, and steryl esters in larvae samples on silica gel with concentration zone, with petroleum ether - diethyl ether - glacial acetic acid 80:20:1 in a twin-trough chamber saturated for 20 min at 21 +/- 1 °C and a relative humidity of 25 %. Detection by spraying with 5 % ethanolic phosphomolybdic acid solution. Quantitative determination by densitometry at 610 nm.

J. Liq. Chromatogr. Relat. Technol. 32, 1273-1288 (2009). HPTLC of Sudan I (1), II (2), III (3), IV (4), Sudan Red B (5), Sudan Red 7B (6), Sudan Red G (7), Para Red (8), FD&C Orange 2 (9), Butter Yellow (10), Citrus Red 2 (11), Toluidine Red (12), and Disperse Orange 11 (13) in paprika, chili, and curry on RP-18 with acetonitrile - ammonia 25 % 19:1. Quantitative determination by absorbance measurement at absorption maxima of each dye. The hRf values of compounds (1) - (13) were 61, 54, 48, 29, 18, 11, 69, 63, 56, 48, 39, 18 and 11, respectively. Visual detection limits were 3 ppm for most dyes in either matrix, 5 ppm for Sudan I, 13 ppm for Disperse Orange, and 7 ppm for Butter Yellow. The limits of detection by densitometry were lower by a factor of 2 for all dyes and values of 1-3 ppm were reached except for Disperse Orange with a limit of detction of 7 ppm. Average recoveries ranged from 95.0-110.8 %. The HPTLC method is successfully applied in the routine control of illegal dyes in food by surveillance authorities.

J. Planar Chromatogr. 24, 352-356 (2011). HPTLC of extracts of dried powdered rhizoms of A. galanga and three phenylpropanoids (1-acetoxychavicol acetate (1), acetoxyeugenol acetate (2), and trans-p-coumaryl diacetate(3)) on silica gel with n-hexane - ethyl acetate 4:1 with chamber saturation for 1 h. After drying second development with the same mobile phase. Quantitative determination by densitometry at the wavelength of maximum absorption. Linearity was between 0.6-1.8 µg/band, 0.4-1.5 µg/band and 0.1-0.3 µg/band for (1), (2), and (3), respectively. The LOD and LOQ was 150 and 500 ng/band for (1), 100 and 334 ng/band for (2), and 23 and 77 ng/band for (3). The repeatability of application and repeatability of measurement (%RSD, n = 6) was 0.9 and 0.5 % for (1), 0.5 and 0.3 % for (2), and 1.8 and 0.9 % for (3). The intra-day and inter-day precision was below 5 % for all compounds. The hRf value was 53, 37, and 43 for (1), (2), and (3), respectively.

J. Planar Chromatogr. 24, 116-120 (2011). HPTLC of rosin, rosarin, and rosavin in the roots of Rhodiola rosea L. and Rhodiola sachalinensis Borissova on silica gel, prewashed with methanol, with chloroform - methanol - water 130:70:21 in a twin-trough chamber lined with filter paper and saturated for 20 min, at 21-24 °C and 40-45 % relative humidity. Quantitative determination by densitometry at 250 nm. The calibrations were linear in the range of 100-500 ng/band with correlation coefficients of 0.9999, 0.9992, and 0.9992 for rosin, rosarin, and rosavin, respectively. Recovery of the three compounds was between 97 and 101 %. The LOD and LOQ were 30 and 100 ng/band, respectively, for all three compounds. The hRf values for rosin, rosarin, and rosavin were 58, 45, and 42, respectively. Intra-day variation, as %RSD, was 2.7 % for rosin, 1.7 % for rosarin, and 2.8 % for rosavin, with standard errors of 0.3 %, 0.2 %, and 0.3 %, respectively. Inter-day variation, as % RSD, was 4.8 % for rosin, 4.2 % for rosarin, and 3.9 % for rosavin, with standard errors of 0.5 %, 0.5 %, and 0.4 %, respectively.

Anal. Chim. Acta 632 (2), 168-180 (2009). Ochratoxins and aflatoxins are the most significant mycotoxins and there has been a broad range of research. However, it is impossible to use one standard technique for the analysis because of the various structures of mycotoxins. The review discusses existing analytical and detection techniques, such as 1) sample pre-treatment methods like liquid-liquid extraction, supercritical fluid extraction, or solid phase extraction; 2) separation methods such as TLC, HPLC, GC, and CE and 3) other methods such as ELISA. The practical requirements for high-sensitivity analysis and the need for a specialist laboratory setting create challenges for routine analysis. There are a number of methods used, but there is no single technique that stands out above the rest, although HPLC-MS is popular. Discussion of further currents trends, advantages and disadvantages and future prospects of these methods.

J. AOAC Int. 93, 820-824 (2010). HPTLC of mexiletine hydrochloride on RP-18 with tetrahydrofuran - citrate buffer (pH 4.45) 3:7 and on amino phase with chloroform - tetrahydrofuran - hexane - ethylamine 30:20:50:1. Quantitative determination by absorbance measurement at 217 nm. Linearity was between 0.5 and 8.0 µg/spot. The accuracy was 99.6 % for the amino phase and 99.5 % for the RP-18 phase. The %RSD of intra-day and inter-day precision was 1.2 and 2.7 %, respectively; for both layers LOD and LOQ were 100 and 300 ng/zone, respectively.

J. Planar Chromatogr. 24, 125-129 (2011). HPTLC of plant extracts and oxyresveratrol on silica gel, prewashed with methanol, with hexane - ethyl acetate - chloroform - methanol 15:10:17:8 in a twin-trough chamber lined with filter paper and saturated for 20 min. Quantitative determination by densitometry at 327 nm. LOD and LOQ were 50 and 200 ng/band, respectively. The hRf value of oxyresveratrol was 31. Intra-day and inter-day variation (%RSD) were consistently below 5.0 %. Within-day precisions for the replicate analysis (n = 3) were in the range of 1.1-4.1 %. Day-to-day replicates (n = 9) were between 2.1-2.8 %.

Food Chemistry 132, 549-553 (2012).. New HPTLC-based method to examine quantitatively the free radical scavenging activity of plant extracts. After chromatographic separation of polar compounds, and immersion of HPTLC plates in methanolic DPPH radical reagent, bleaching was observed and recorded using a photo camera and data analysis was carried out using an image processing software. The method is simple, fast and efficient for free-radical scavenging activity analysis of phytochemicals and crude plant extracts.