J. Liq. Chromatogr. Relat. Technol. 31, 2673-2685 (2008). TLC of dehydroepiandrosterone on silica gel with chloroform - acetone 17:3 with chamber saturation for 30 min. Detection by dipping into 0.05 % aqueous solutions of visualizing agents (methylene violet, gentian violet, janus blue, methylene blue, malachite green, rhodamine B) and methanolic chloramine T/methanolic sulfuric acid solution. Quantitative determination by densitometry at 200 nm (before derivatization and for methylene violet), 657 nm (gentian violet), 487 nm (janus blue), 488 nm (malachite green), 580 nm (rhodamine B), and 361 nm (chloramine T). LOD was 0.29 µg/zone (without visualizing agent, with chloramine T and with rhodamine B), 4.19 µg/ zone with methylene violet, 1.10 µg/zone with gentian violet, 2.14 µg/zone with janus blue, and 4.19 µg/zone with malachite green, all with an application volume of 5 µL.

Chinese J. Pharm. Anal. (Yaowu Fenxi Zazhi) 8, 337-340 (1988). TLC on silica with dichloromethane - acetone 8:1 and 45:1. Detection by spraying with sulfuric acid - ethanol - water and heating at 120°C for 10 min. Quantification by densitometry at 550 nm.

Anal. Biochem. 224 , 455-457 (1995). TLC on silica with 1) chloroform - acetone 9:1, followed by dichloromethane - ethyl acetate - ethanol 14:4:1; 2) chloroform - ethyl acetate 4:1. Detection under UV 254 nm or by exposure to iodine vapor. The procedure can be used for the identification of specific forms of cytochrome P450 in crude microsomal preparations, as well as for monitoring the purification of new forms of the enzyme and alterations in the catalytic activities of mutagenically altered forms of the enzyme.

J. Liq. Chromatogr. Relat. Technol. 37, 2872-2881 (2014). 2D-HPTLC of 17 alpha-ethinylestradiol on RP-18 with methanol – acetonitrile – water 2:2:1 in the first direction and cyclohexane – butyl acetate – methanol 8:6:1 in the second direction, both over 70 mm. With the grafted method both plates were combined in a 2D separation. Detection by dipping into a mixture of sulfuric acid (98 %) and water (1:49), followed by heating at 110 °C for 10 min. Compound was also detected using a yeast estrogen screening assay using the strain Saccharomyces cerevisiae BJ3505.

J. Pharm. Biomed. Anal. 8, 253-257 (1990). A densitometric method for determination of complex mixtures of conjugated oestrogens in raw material and tablets was developed. The proposed procedure comprised hydrolysis of sodium sulfate esters of oestrogens and oestradiol, equilenin, 17a-dihydroequilenin, the chloroform extraction of free oestrogens and methyltestosterone (internal standard). TLC on silica with chloroform - cyclohexane - dioxane - triethylamine 45:40:10:6. Quantification by densitometry at 254 and 280 nm. Detection limit 0.06 µg, recoveries 97,1% (conjugated oestrogens) and 103,2% (tablets). The proposed method is simple, rapid, and reproducible.

J. Liq. Chromatogr. Relat. Technol. 30, 2629-2634 (2007). TLC of ergosterol, stigmasterol, dihydrocholesterol, 4-cholesten-3-one, cholecalciferol, and cholesterol acetate on silica gel using methanol - dichloromethane 1:19 in a saturated horizontal chamber. Detection by spraying twice with 10 % phosphomolybdic acid in methanol and heating. Contrary to the data reported in literature, the experiments revealed that the best conditions for robust detection of these analytes are achieved if the TLC plates are heated at relatively low temperatures (between 40 and 80 °C) and for longer times (more than 20 min).

J. Chromatogr. A 1530, 192-196 (2017). HPTLC to measure the antioxidant and hypoglycemic effects in different extracts from Myrmecodia platytyrea, which can be a traditional medicine as alternative treatment for diabetes, because the substances produced by ants can reduce blood sugar levels. Measurement of the antioxidant activity in methanol, ethanol, dichloromethane (DCM) and ethyl acetate (EA) extracts with the HPTLC-2,2-diphenyl-1-picrylhydrazyl free radical (DPPH*) assay, and of the hypoglycemic effects with a newly developed α-amylase inhibitory activity assay. Detection of stigmasterol after derivatization with anisaldehyde reagent as purple colored zone under white light at hRF 66. The results showed the highest antioxidant activity in the ethanol extract rich in polyphenols and flavonoids. No antioxidant activity but significant α-amylase inhibitory activity was observed in the DCM extract. The highest α-amylase inhibitory activity was found in the EA and DCM extracts and was related to their stigmasterol content.

Proc. Intern. Symposium on TLC with special Emphasis on OPLC, Szeged, 83-84 (1984). TLC of ecdysteroids on silica with a) chloroform - dichloromethane - methanol 85:10:5, b) ethyl acetate - methanol - NH3 85:10:5. Detection by UV. Method of choice for screening.