J. Planar Chromatogr. 29, 361-365 (2016). Analysis of phenols in bio-oil from agricultural wastes obtained during fractionation. Column chromatography (CC) on silica gel in a glass column (i.d. 1 cm, 50 cm length) filled with n-hexane. The concentrated organic phase was mixed with silica gel 1:1, loaded onto the column and successively eluted with dichloromethane – acetone 20:1, ethyl acetate, and methanol. 24 eluate fractions were obtained during the fractionation using CC, 12 with dichloromethane – acetone mixture, 5 with ethyl acetate, and 7 with methanol. Phenolic compounds were present only in the dichloromethane – acetone mixture fraction which was therefore selected as the proper eluent to obtain all the phenolic fractions dissolved. To monitor the fractionation, TLC of the eluates on silica gel in saturated chambers (mobile phase not specified) to a distance of 4 cm. Qualitative identification under UV 254 nm and by exposure to iodine vapor. The hRf values of the standard solutions of phenol, cresol and guaiacolin dichlorlomethane were 66, 68 and 78, respectively. Eluate fractions were further analyzed by GC–FID and GC–MS.

Part II: Remijia ferruginea. Rev. Bras. Farmacogn. 27, 153-157 (2017). HPTLC fingerprint of Remijia ferruginea on silica gel with ethyl acetate – toluene – formic acid – water 12:4:4:3. Detection by spraying with natural product reagent, followed by PEG reagent. The hRF values for rutin, chlorogenic acid and cinchonine were 50, 60 and 65, respectively.

J. Chromatogr. A 1532, 198-207 (2018). Development of a method to analyze the efficiency of a diverse set of natural deep eutectic solvents (NADES) for the extraction of compounds of interest from two model plants, Ginkgo biloba and Panax ginseng. HPTLC on silica gel with toluene – ethyl acetate – acetone – methanol 50:25:25:3 for ginkgolides in Ginkgo biloba leaves; with ethyl acetate – acetic acid – formic acid – water 100:11:11:27 for phenolics in Ginkgo biloba leaves; with toluene – ethyl acetate – acetic acid 40:10:1 for ginkgolic acids in Ginkgo biloba leaves; with chloroform – ethyl acetate – methanol – water 15:40:22:10 for ginsenosides in Panax ginseng leaves and stems. The six different NADES were combinations of two or three compounds mixed in defined molar ratios, e.g. malic acid – choline chloride 1:1, malic acid – glucose 1:1, choline chloride – glucose 5:2, malic acid – proline 1:1, glucose – fructose – sucrose 1:1:1 and glycerol – proline – sucrose 9:4:1. Processing the data obtained by multivariate data analysis showed differences between the extracts. Discussion of the foreground of application of NADES in green chemistry and the advantages of NADES as green solvents used in novel green products for the food, cosmetics and pharmaceuticals.

J. Liquid Chromatogr. 6, 1171-1174 (1983). TLC of 3-and 4-isomers of 2-cyclopentylphenol on silica with chloroform - ethyl acetate 95:5. Detection with iodine vapors. Visualization under UV 254 nm.

J. High Resol. Chromatogr. 10, 404-408 (1987). TLC separation of 16 phenolic compounds (dianes, biphenyl and its hydroxy derivatives, naphthalene and its hydroxy derivatives and nitrophenols) on RP-18 with eluents containing tensides in water/methanol mixtures. Detection via the Boute reaction and UV 366 and 254. nm

J. Chromatogr. 464, 220-222 (1989). TLC of benzene derivatives containing more than one hydroxy and a carboxy group in different positions and carboxy group not directly attached to benzene ring on plain and iron(III)-impregnated silica with distilled, tap and sea water. Calculation of the Rf values.

Chromatographic separation of nitrophenols. J. Chromatogr. 558, 415-522 (1991). Comparison of the chromatographic behavior of nitrophenols on silica and cellulose layers. both with and without impregnation with non-aqueous polar and less polar stationary phases. Investigation of the behaviors and the problems encountered in different systems. Polar stationary phases used: formic acid, dimethylformamide, etc.; less polar stationary phases used: liquid paraffin, octan-1-ol, 1-bromonaphthalene.

J. Planar Chromatogr. 6, 372-377 (1993). TLC of phenol, 2-cresol, 4-cresol, 1-naphthol, and leachates (after oxidative coupling with 3-methyl-2-benzothiazolinone hydrazone, MBTH) on silica with dichloroethane. For certain phenols with very similar Rf values increased resolution could be achieved by multiple elution. In-house evaluation was performed by densitometry in absorbance mode at 500 nm.