Chinese J. Chromatogr. 7, 313-314 (1989). TLC on methyl-benzylethyl dichlorosiliane-bonded silica with perchloric acid or benzene sulfonic acid as counter-ion and mixture of ethanol - water as mobile phase. Discussion of chromatographic behavior depending on the composition of the mobile phase.

J. AOAC Int. 77, 1335-1337 (1994). TLC of 11 synthetic colors (FD&C Blue No.1, No. 2, Green No. 3, Red No. 1, 2, 3, 4, and 40, Yellow No. 5, and 6, Patent Blue V) on silica with 1) 1-butanol - 2-butanol - acetonitrile - tetrahydrofuran - ethyl methyl ketone - NH3 - 0.5% aq. sodium chloride 10:10:25:15:20:2:18 or 2) 1-butanol - ethyl methyl ketone - NH3 - water 5:3:1:1. Chamber saturation for 30 min. Detection limit < 1 ppm.

J. Planar Chromatogr. 15, 120-123 (2002). HPTLC of 18 amines (o-, m-, p-chloroaniline, o-, m-, p-toluidine, o-, m-, p-anisidine, 1-, 2-naphthylamine, 3-, 4-,5-chloro-o-toluidine, 2,4-, 2,6-diaminotoluene, 2-amino-4-, and 2-amino-5-nitrotoluene), seven of them prohibited under a German ban, on silica gel impregnated with a 0.1 M solution of 18-crown-6 in methanol, in a pre-saturated TLC chamber, with benzene for the first development, and, after drying with toluene for the second development. Quantitation by densitometry at 254 nm in absorbance-reflectance mode. Addition of 18-crown-6 improves the separating power of the stationary phase.

Spectroscopy and Spectral Anal. 30(12), 3254-3257 (2010). Dye analysis is important for the understanding of fabric color degradation and technical development of ancient printing and dyeing. TLC of blue dyes extracted from 6 silk fabrics of the Tang dynasty and decorative paintings of Jian Fu Gong (Forbidden City) on silica gel with benzene – nitrobenzene – acetone 8:1:1. Identification of indigo by comparison of the colors and the Rf value with the zone by the standard, and by Raman spectroscopy of raw samples. Raman spectroscopy is a nondestructive analysis whereas TLC requires small amounts of sample but may give more information. Both methods may be applicable for cultural heritages. The results obtained indicate that all these blue substances are indigo, which was not only used as dye in ancient fabrics, but also as pigment in decorative painting of historic buildings.

Study of the carotenoids giving the red colour to ground red pepper. Acta Alimentaria 17, 37-41 (1988). OPLC of capsanthin and capsorubin on silica with petrol ether - benzene - acetone - acetic acid 40:10:2:2.5. Quantification by spectrophotometry after elution. Recoveries: capsanthin 95,2% ± 2,99%, capsorubin 91,8% ± 3.88%.

Planta Med. 55, 41-43 (1989). TLC of proanthocyanins on silica with ethyl acetate - formic acid - acetic acid - water 75:1:1:23. Detection with vanillin - sulfuric acid reagent.

J. Agric. Food. Chem. 42, 1089-1095 (1994). TLC isolation of chlorophyll a and b on silica with petrol ether (65-95°) - acetone - dimethylamine 10:4:1.

J. Planar Chromatogr. 9, 48-51 (1996). TLC of 7,7'-biphysicon, physicon, chrysophanol on silica with chloroform - ethyl acetate - formic acid 89:10:1. After cutting the plate into two pieces 7.0 cm from the bottom edge, the upper portion was developed with the same solvent for 1.0 cm, and after drying with hexane - ethyl acetate - formic acid - water 178:20:2:7. Quantification by densitometry at 430 nm and a reference wavelength of 540 nm. Detection limit in the lower nanogram range (5 - 10 ng).