Sz. Nyiredy, A. Kakuk (eds.): Planar Chromatography 2000, Lillafüred, Hungary, 24-26 June 2000, Res. Inst. for Med. Plants, p. 231-235. Validated HPTLC on silica gel with ethyl acetate - methanol - acetic acid 80:19:1 for ca. 15 min. Quantitation by absorbance measurement at 300 nm (polynomial regression). Recovery was found to be between 99,0 and 101,3 %, repeatability was 0,1 % for aspirin and 2,2% for salicylic acid (n=2). HPTLC method is preferred to HPLC method because of its speed (14 samples in 30 min).

Chromatographia 75 (9-10), 449-456 (2012). Proposal of application of OPLC and TLC techniques with micellar mobile phases to evaluate the lipophilicity of 21 newly synthesized 1,2,4-triazoles, compounds of potential importance in medicine or agriculture as fungicides. The separation of the compounds 1) by micellar TLC on cyano phase with buffered SDS – tetrahydrofuran 4:1 in a sandwich chamber; 2) by micellar OPLC on cyano phase with buffered SDS - tetrahydrofuran 4:1 in off-line mode; 3) by reversed-phase TLC on RP-8 phase with buffered solutions of acetonitrile and tetrahydrofuran in concentrations varied in the range of volume fraction from 0.3 to 0.7, in constant steps of 0.1. Detection by densitometric scanning at UV 200 nm, or by means of a video camera at UV 254 nm. Application also of micellar HPLC technique on RP-8 column eluted with buffered SDS - acetonitrile 4:1, whereas in OPLC and TLC, cyano phases were applied, which allowed the use of micellar effluents in planar chromatography measurements. Determination of the micellar parameters log km and comparison with extrapolated R M0 values determined from reversed-phase TLC experimental data, as well as with log P values (Alog Ps, AClog P, Alog P, Mlog P, KowWin, xlog P2 and xlog P3) calculated from molecular structures of solutes tested. Application of principal component analysis (PCA) and linear regression showed the results of considerable similarity between partition and retention parameters as alternative lipophilicity descriptors, and indicated micellar chromatography as a suitable technique to study lipophilic properties of organic substances.

J. Chromatogr. 258, 43-55 (1983). Comparison of eight types of commercially available thin-layer plates pre-coated with non-polar chemically bonded phases. Phthalate esters,aromatic acids, chlorophenols, chloroanilines and aminophenols were used as test compounds.

J. Liquid Chromatogr. 6, 2665-2677 (1983).TLC of naphthalene, º-methylnaphthalene, pyrene, chrysene, fluoranthene, diphenyl (as model substances) on silica with a) hexane - benzene,b) methylcyclohexane - benzene, c) benzene - methanol, d) benzene - ethanol.

J. High Resol. Chrom. 10, 560-563 (1987). Discussion of several methods for evaluating separation quality in two-dimensional TLC.

J. Planar Chromatogr. 7, 305-308 (1994). Calculation of specific heats and adsorption energies for different TLC systems comprising fifteen different ternary solvents containing ethyl acetate, chloroform, tetrahydrofuran and hexane. The heat capacities of the systems were quite logically affected by the solvents. They increased as volumes of ethyl acetate and tetrahydrofuran were increased. The highest adsorption energy was found for the system comprising silica gel with pure tetrahydrofuran as eluent.

Anal. Bioanal. Chem. 391, 2111-2118 (2008). Review of developments in planar electrochromatography in open (PEC) and closed (PPEC) systems regarding the progress in chamber construction for planar electrochromatography, separating system performance, equilibration of the PPEC process, separation time and selectivity, and the general advantages, disadvantages and prospects of this separation mode. PPEC of 4-cholesten-3-one, 4-androsten-17alpha-ol-3-one acetate, 17R-acetoxyprogesterone, androstenedione, 4-pregen-11R-ol-3,20-dione, benzanilide, o-nitroaniline, hydrocortisone alcohol, and benzamide on RP-18 with 55 % aqueous acetonitrile containing 5 mM acetate buffer (pH 4.7) at 9 kV and under a pressure of 63 atm.

Comparison of the extrapolated Rm values. J. Chromatogr. 347, 209-218 (1985). Rm determination of a series of prostaglandins in two reversed-phase TLC systems, the mobile phase being an aqueous buffer alone or mixed-with various amounts of methanol or acetone. Discussion of the relationship between chromatographic behaviour and mobile phase composition. The extrapolated Rm values are independent of the nature of the organic solvent