J. Liq. Chromatogr. Relat. Technol. 36, 2476-2488 (2013). HPTLC of synthetic colorants tartrazine (1), quinoline yellow (2), sunset yellow FCF (3), azorubine (4), amaranth (5), ponceau 4R (6), allura Red AC (7), patent blue V (8), indigo carmine (9), and brilliant blue FCF (10) on RP-18 with 0.5 M ammonium sulfate in 30 % of ethanol - water solution. Quantitative determination by absorbance measurement at 450, 500 and 625 nm. The hRf values were in the range of 17 and 64. Linearity was in the range of 20-180 ng/zone for (1) to (8) and 35-300 ng/zone for (9) and (10). LOD and LOQ were 2 and 3 ng/zone, respectively. Recovery (by standard addition) was in the range of 81-108 %. Intermediate intra- and inter-day precision was below 5 % (n=3).

J. Liq. Chromatogr. Relat. Technol. 40, 239-246 (2017). Review of TLC methods for the analysis of polyphenols, dyes, carboxylic acids, biogenic amines, and vitamin C in quality assessment and authentication of non-fermented or fermented beverages derived from fruits.

(Chinese). Chinese J. Chromatogr. 6, 121-123 (1988) (Sepu). TLC of bromamine acid and its impurities on silica with ethyl acetate - ethylhexanol - acetic acid - water 2:1:1:1, and ethyl acetate - petrol ether 1:5. Quantification by densitometry at 260 nm.

Proc. 6th Int. Symp. Instrum. Planar Chromatogr., (Interlaken 1991), Inst. Chromatogr., Bad Dürkheim, FRG, 385-399 (1991). HPTLC of thiazine dyes on silica. Methylene blue, azure A, B, C and toluidine blue were separated with butan-1-ol - acetic acid - water 50:5:10 and methylene violet with butan-1-ol - formic acid - water 50:5:5. Scanning by absorbance at 540 and 620 nm.

GIT Fachz. Lab. Spez. Chrom. 2/96, 126-129 (1996). Combination of conventional TLC, with subsequent color detection and HPTLC, using AMD and densitometry. - HPTLC screening of amines after reductive cleavage of azoic dyes on silica with dichloromethane - acetonitrile 25:3; detection by coupling with (1-naphthyl)-ethylene diammonium dichloride. Confirmation of positive samples by AMD using a 15-step gradient. Quantification by densitometry at 200, 230, and 300 nm. As alternative TLC with diisopropylether - pentane - diethylamine 12:8:1.

CBS 88, 7 (2002) HPTLC of E 110 Yellow orange S, E 104 Quinoline yellow, E 124 Cochineal red, E 132 Indigotine I, E 151 Brilliant black BN on RP-18 W with methanol - 5 % aqueous sodium sulfate solution 3:4. Identification based on Rf-values, documentation under white light.

J. Sep. Sci. 30, 3311-3315 (2007). HPTLC of lawsone in the leaves of Lawsonia alba on silica gel with chloroform – methanol 17:3. Quantitative determination by absorbance measurement at 334 nm. The hRf value of lawsone was 40 and selectivity regarding matrix was given. Linearity was between 100 and 1000 ng/zone. The precision was 1.72 % and recovery (by standard addition) was 98.8 %.

Chinese Bulletin of Biol. 47 (7), 44-46 (2012). Chloroplast pigments play an important role in plant photosynthesis and become a kind of main raw material widely applied in the preparation of antitumor photodynamic drugs and functional foods. Phytoxanthin has outstanding function in vision protection, reducing the incidence of cataracts, anticancer therapy, and delaying the occurrence of arteriosclerosis. As a demonstration experiment for high school students analysis of chloroplast pigments by TLC and column chromatography. TLC of the extracts of fresh spinach leaves on silica gel with petroleum ether (30-60 °C) – benzene – acetone 7:1:5, detection in daylight, identification of beta-carotene (orange), chlorophyll a (dark green), chlorophyll b (light green) and phytoxanthin (bright yellow) by fingerprint comparison with the standards. Preparation by column chromatography on silica gel eluted with the same sovent system, collection of fractions, and the pure products were obtained by solvent evaporation. The results indicate that the TLC method is simple, sensitive, easy to operate, more intuitive, robust and more suitable for the purpose.