J. Liq. Chromatogr. Relat. Technol. 31, 555-566 (2008). Five new derivatization reagents (gentian violet, methylene violet, methylene blue, malachite green, and Janus blue) were used to detect estradiol on aluminium oxide. Barton’s reagent, rhodamine B, and sulfuric acid were used as the comparative derivatization reagents. Limit of detection, detection index, modified broadening index, modified contrast index, and linearity range were determined for estradiol after derivatization with these reagents. Quantitative determination by absorbance measurement between 200 and 600 nm.

behavior of some steroids by OPLC. Proc. Intern. Symposium on TLC with special Emphasis on OPLC, Szeged, 90 (1984). OPLC (OPTLC) of progesterone, cholesterol, corticosterone, aldosterone, cortisol, cortisone on silica with a) petrol ether - ethyl-acetate 6:4, b) chloroform - ethyl acetate - ethanol 90:10:1, c) chloroform - phenol 9:1. Detection with 50 % phosphoric acid and heating at 105 °C for 15 minutes.

Planta Medica 82 (16), 1395-1402 (2016). The hexane – ethyl acetate subfraction of the ethyl acetate fraction of an ethanolic Tabebuia roseoalba leaf percolation extract was subfractioned on a silica gel column with 42500 mL of a gradient of hexane, ethyl acetate, and methanol. For monitoring, TLC on silica gel with hexane – ethyl acetate 1:1, detection with anisaldehyde sulfuric acid reagent. Two fractions that gave only one visible zone on TLC, were identified by NMR as mixtures of stigmasterol and sitosterol, and of alpha- and beta-amyrins, respectively.

Lipids 17, 448-452 (1982). Purification of hexadecyl cholesteryl ether by silica column chromatography for removing the majority of unreacted hexadecylmethane sulfonate and dihexadecyl ether by-product. TLC on silica with hexane - ether acetic acid 80:20:1. Typical overall product yield 60-80 % of the theory. Product resistant to acid hydrolysis in 7 % HCl in methanol for 4 h at 60 °C, conditions that hydrolize cholesteryl oleate.

H. TRAITLER, A. STUDER, R.E. KAISER (eds): Instrumental HPTLC, Institute for Chromatography, Bad Dürkheim, FRG (1987), 35-41. TLC on silica with ether - benzene - cyclohexane 90:10:1. Detection by spraying with an aqueous solution of saturated copper acetate - orthophosphorous acid 5:5 and heating. Evaluation by densitometry using 7 ß-hydroxydehydroepiandrosterone and 3a-11ß-20ß-trihydroxy(5ß) pregnane as internal standards. Sensitivity, 200 ng.

Chem. Anal. (N.Y.) 108, 15-47 (1990). A review with 8 references on the use of surface-modified reversed phase sorbents for HPTLC. Discussion of the surface reactions. Application in the separation of cholesterol and its bile acid metabolites and a mixture of steroids.

J. of Natural Products 57, 620-628 (1994). Preparative TLC separation of closely related 7-hydroxy sterols on silica with hexane - ethyl acetate 7:3 and on RP-18 silica with 95% aqueous methanol.

J. Planar Chromatogr. 12, 416-410 (1999). HPTLC of cholesterol on silica gel with petroleum ether - ether - acetone 90:10:1 in an unsaturated chamber. Detection by spraying with a 10% solution of phosphomolybdic acid in ethanol and drying at 100°C. Quantification by densitometry at 580 nm.