J. Liq. Chrom. Rel. Technol. 27, 1993-2002 (2004). Commercially precoated TLC and HPTLC silica gel plates, with enhanced brightness UV indicator were compared with comparable plates formulated with standard indicators. Results showed that the increased UV indicator plates had visually brighter backgrounds, however, the limits of detection did not improve. HPTLC and TLC on silica gel of caffeine and acetaminophen with ethyl acetate - glacial acetic acid 19:1, and salicylamide with methylene chloride - acetone 4:1 in a twin-trough chamber containing a saturation pad. Quantitative determination at 254 nm.

J. Planar Chromatogr. 28, 234-240 (2015). HPTLC of (1) omeprazole, (2) pantoprazole, (3) rabeprazole and (4) diclofenac from tablets on silica gel previously washed with methanol and activated at 105 °C for 20 min, with toluene - n-butanol - 25 % ammonia 30:70:2. Quantitative determination by absorbance measurement at 290 nm. The hRF values were 67 for (1), 38 for (2), 57 for (3) and 27 for (4). Linearity was between 50 and 500 ng/zone for (1), (2) and (3), and between 150 and 1500 ng/zone for (4). The interday and intraday precisions were below 2 %. The LOD and LOD respectively for (1) were 7 ng/zone and 24 ng/zone, for (2) 9 ng/zone and 30 ng/zone, for (3) 13 ng/zone and 43 ng/zone, and for (4) 25 ng/zone and 82 ng/zone. Recovery was 99.6 % for (1), 100.1 % for (2), 100.4 % for (3) and 100.1 % for (4).

J. Liquid Chromatogr. 14, 3213-3239 (1991). Proposal of a new combination of four organic solvents for the optimization of TLC separations of basic drugs and alkaloids using response surface modelling and mixture designs. Adjustment of solvent strength and selectivity using a four component mixture space of tetrahedron. Discussion of the selection of the four solvents defining the factor space, the selection of the design space and of the experimental design, the optimization criterion, and the POEM software used for modelling the response surface and locating the optimal solvent composition.

J. Planar Chromatogr. 6, 296-299 (1993). Integration of four computer-assisted methods (the monofactor optimization system (MOS); the multicomponent solvent optimization system (MSOS); the difactor optimization system (DOS); and the stepwise gradient optimization (SGOS)) for optimizing HPTLC separation in order to produce the optimization system of TLC (OS T), resulting in a method development strategy which obtains simple solutions for simple separation problems and reserves the more complex solutions for difficult separations.

Proc. 9th Internat. Symp. Instr. Chromatogr., Interlaken, April 9.-11., 337-339 (1997). Prediction of retention data using multiple development and circular techniques from a single development.

J. Planar Chromatogr. b, 178-182 (2001). Evaluation of molecular interactions in liquid adsorption chromatography with mixed mobile phases. Two equations based on different retention mechanism models were verified experimentally. TLC on silica gel; development in horizontal chambers with cyclohexane - carbon tetrachloride, cyclohexane - ethylene chloride, n-heptane - ethylene chloride, and n-heptane - acetone.

2: Comparison of some parameters in OPLC and TLC. J. Planar Chromatogr. 6, 256-258 (1993). Investigation of the linearity of the calibration graph, the limits of detection and quantification and the precision of the data of an OPLC purity test during the development of chromatograms at different flow rates. The best results (lowest LOD and LOQ as well as the best precision) were obtained by OPLC when eluting with the optimum linear velocity. Quantification by densitometry at 237 nm.

Proc. Intern. Symp. on Planar Separations, Planar Chromatography 2001, pp. 91-101. HPTLC of sodium glutamate on silica gel. Quantitative TLC is considered as a typical separation technique where evaluation of uncertainty can be done with seriously planned validation. The contributions of sources calculated according to guidelines are so small that their effects on the final results are negligible.