J. Planar Chromatogr. 13, 231-234 (2000). RPHPTLC on RP 18 with methanol - water mixtures. The concentration of methanol in the mobile phase ranged from 50 to 90 % in steps of 10 %. Visualization under UV.

Acta Chromatographica 14, 16-36 (2004). Study on co-elution by using two binary mixtures which can form mixed associative structures by hydrogen bonding: 1) a carboxylic acid (2-phenylbutyric acid) and a ketone (benzophenone), and 2) an aliphatic alcohol (5-phenylpentanol, and the same ketone (benzophenone). By using mild chromatographic conditions and working in the non-linear region of the adsorption isotherm, the co-elution of the two analytes from each pair in the form of a single chromatographic band was demonstrated, three different physicochemical explanations of their densitometrically measured concentration profiles were suggested, and semi-quantitative simulations of these profiles were performed. Discussion and comparison of the experimental results obtained by planar chromatography and HPLC using fully analogous working conditions.

J. Planar Chromatogr. 18, 212-216 (2005). Retention factors on RP-18 layers corresponding to zero percent organic modifier in the aqueous mobile phase were determined for five mobile phase mixtures: methanol - water, acetone - water, acetonitrile - water, 2-propanol - water, and tetrahydrofuran - water and relationships between the retention factors obtained with different organic mobile phase modifiers were examined. A variety of partition coefficients were calculated by use of different software products and the correlation between these partition coefficients and chromatographically obtained lipophilicity was analyzed. On the basis of of correlations between retention factors and the partition coefficient log P, RP-18 with methanol - water as mobile phase was selected as the best RP-HPTLC system for determination of the octanol/water partition coefficient and thus the lipophilicity of the molecules. Visualization under UV light at 254 nm.

Part III – a study on CN adsorbent layers. J. Planar Chromatogr. 25, 471-474 (2012). TLC of 35 simple compounds with known literature lipophilicity on cyano phase with increasing mixtures of methanol - water. Detection by absorbance measurement at 254 nm. Correlation between single RM values and lipophilicity values as well as dependences between the extrapolated log kW and experimental lipophilicity was described.

J. High Resol. Chromatogr. 10, 560-563 (1987). Discussion of several methods for evaluation of separation quality in 2D-TLC using either the distance between spot centers for the pair of solutes which is the most difficult to separate in a mixture or the value of a suitable separation function as criteria of overall separation quality. Contour diagrams constructed from solvent composition and spot separation should be of value for comparing different solvent systems.

Effect of surface pH of silica. J. Chromatogr. 520, 249-256 (1990). Determination of the lipophilicities of 22 peptides by reversed-phase TLC on silica with surface pH values 2.0, 4.5, 7.5 and 9.0, using methanol as organic modifier in the concentration range 0 - 90 Vol.-%. Effects discussed: proportion of the organic modifier on the RM value of the peptides - influence of the peptide structure - surface pH of the silica on the silanophilic effect - influence of the presence of a ring structure, of the over all polarity and of the number of amino acids in the peptide.

J. Planar Chromatogr. 5, 323-333 (1992). Discussion of methods commonly used to determine the observed plate height in TLC including problems arising in experimental measurements. At present it seems reasonable to conclude that none of the reported methods provides an adequate description of the average plate height for TLC.

J. Planar Chromatogr. 8, 336 - 340 (1995). Introduction of a new model of solute retention for RPTLC with (B + AB)-type mobile phase. On the basis of theoretical assumptions physico-chemical relationships were derived for solute Rf values in RPTLC with acetonitrile - water, tetrahydrofuran - water, and acetone - water. The practical utility of the model has been demonstrated with abundant experimental results. Excellent agreement was observed between experimental and predicted Rf values for test solutes. - RPTLC of naphthalene, anthracene, phenanthrene, chrysene, and pyrene on RP-18 silica developed with ACN - water, THF - water, and acetone - water mixtures of different ratios.