A comparative study. J. Chromatogr. 635, 165-170 (1993). Two-dimensional TLC maps of dansyl chloride-, dabsyl chloride- and 7-chloro-4-nitrobenzoxazole - derivatised amines on silica with 9 solvent systems. Evaluation of some factors which influence sensitivity. Recommendation of dansyl chloride as the reagent for chromatographic analysis of complex mixtures of biogenic amines.

Anal. Letters 31, 475-489 (1998). HPTLC of plant tissues, dansylated in a microwave oven, on silica with chloroform - triethylamine 2:1. Quantitation by in situ densitometry at 338/>502 nm. Detection limit 1.8 - 3.0 ng. Precision 0.75-1.39%.

CBS 93, 5-7 (2004). HPTLC of N,N-diethylethane-1,2-diamine in metoclopramide finished products on silica gel with 32 % ammonia - methanol - dichloromethane 3:15:80 over 40 mm with chamber saturation. Detection by dipping in 0.2 % ethanolic ninhydrin solution for 1 s, followed by drying at 120 °C for 5 min. Quantitative determination by absorbance measurement at 480 nm and evaluation of peak area with polynomial regression. The correlation coefficient of the calibration curve is 0.9995, the residual standard deviation 2.19 %. Intermediate precision is 1.65 %. Recovery for 0.2-1.0 % impurity is 100.5 %. Limit of quantitation is 0.05 % impurity.

J. AOAC Int. 92, 725-729 (2009). HPTLC of acrylamide extracted from coffee samples on silica gel with ethyl acetate - tert. butyl methyl ether 4:1 in a twin trough chamber or automatic developing chamber. Pre-chromatographic in situ derivatization of the extracts (applied as area) by overspraying with dansulfinic acid produced the fluorescent dansylpropanamide band. Quantitative determination by fluorescence measurement at 254/>400 nm. The limit of quantification was 48 µg/kg. The linearity over the whole procedure showed determination coefficients between 0.9995 and 0.9825 (n = 6). The within-run precision (%RSD, n = 6) of the chromatographic method was 3%. Commercial coffee samples analyzed showed acrylamide contents between 52 and 191 µg/kg, which was in correlation with amounts reported in publications.

J. Planar Chromatogr. 24, 435-440 (2011). TLC of nine N-cyclohexyl-N-substituted-2-phenylacetamides on RP-18 with different aqueous eluents; water - acetone, water - acetonitrile, and water - dioxane. The volume fraction of the organic modifier in the aqueous mobile phase comprised 60-80 % (dioxane, acetone) and 70-90 % (acetonitrile) and varied in steps of 5 %. Detection under UV light at 254 nm. The effects on retention behavior of all investigated modifiers were similar. The linear relationship between retention parameters and organic modifier content allowed the extrapolation procedure. The result of the investigation showed that reversed-phase RM0 proved to express the lipophilic nature of an investigated compound as well as its biological activity.

Planta Med. 83, 1097-1102 (2017). The fractionations on a silica gel column (with a gradient of ethyl acetate, methanol and petroleum ether/dichloromethane) of the dichloromethane and methanol extracts of Antidesma ghaesembilla bark were monitored by TLC on silica gel with chloroform – methanol – water – formic acid 290:20:1:1 or 290:50:1:1, respectively. From fractions of the dichloromethane extract, chavibetol, sitostenone, asperphenamate, daucosterol, 5,7-dimethoxy-aristolochic acid II and 10-amino-5,7-dimethoxy-aristolic acid II were later isolated, the last one was detected by Dragendorff reagent. From fractions of the methanol extract, glucosides of aristolic acid and of vanillic acid were isolated and separated by preparative TLC with chloroform – methanol – acetone – formic acid 450:75:25:2. This preparative TLC yielded protocatechuic acid (hRF 51) and a mixture (hRF 14–19), from which a methyl-phloroglucinol glucoside was isolated by gel exclusion chromatography.

J. Liquid Chromatogr. 15, 1621-1638 (1992). TLC and HPTLC of title substances on silica with different solvent compositions. Detection by spraying with orcinol ferric chloride reagent, by densitometry at 550 nm, and immunostaining.

CBS 90, 2-4 (2003). HPTLC-AMD on silica gel with a 11-step gradient with chloroform - ethanol - acetone followed by 3 isocratic steps with chloroform for separation of cholesterol, cholesterol sulfate and various ceramide classes. For separation of cholesterol, fatty acids, triacylglycerol, cholesteryl esters, and squalene a 2-step gradient with n-hexane - ethyl acetate followed by an isocratic step with n-hexane. Conditioning between single runs with 4 M acetic acid. Detection by dipping in copper sulfate reagent followed by heating at 150 °C for 20 min. Quantitative determination by absorbance measurement at 546 nm.