J. Planar Chromatogr. 7, 450-452 (1994). Preparation of a stationary phase for TLC by bonding purified volcanic tuff (rich in silica gel) with 1-octene; characterization by elemental analysis, measurement of specific surface area, and by chromatographic testing.

J. Planar Chromatogr. 9, 107-112 (1996). Examination of the adsorption properties and separating ability of silica modified by addition of sodium hydrogen carbonate. The retention of the chosen 20 alkaloids was examined by the use of a nonaqueous mobile phase and by optimization of the systems by changing the identity and concentration of the modifier. Detection under 254 or 366 nm or with Dragendorff's reagent. Results obtained in the study were used to determine programs for stepwise and multiple-development gradients suitable for the separation of a complex alkaloid mixture.

J. Planar Chromatogr. 12, 255-260 (1999). (1994) Modification of a sorbent Study of the conditions for the modification of polyamide with Co(II), Cu(II), and Zn(II) salts. Determination of the effect of impregnation time and concentration of the metal ion solution and test of the chromatographic properties on selected sulfonamides.

Part I. Comparison of separations of fatty acids on RP-18 plates with and without a concentrating zone. J. Planar Chromatogr. 15, 332-340 (2002). Fatty acids from pentanoic acid to tricosanoic acid have been separated on RP-18 with and without concentrating zone. Visual inspection of the chromatograms revealed that better separation of the acids was obtained on RP-18 plates with concentrating zones because compact chromatographic bands were obtained. TLC of 19 fatty acids on RP-18 with methanol - water 9:1; 19:1 or methanol. Visualization by exposure to iodine vapor.

J. Planar Chromatogr. 19, 324-326 (2006). GC-MS investigation of dichloromethane extracts from three different types of RP-18 modified silica gel used as TLC adsorbents. Alkenes and carbonyl compounds (two different aldehydes and one ketone) were identified.

J. Planar Chromatogr. 7, 157-159 (1994). TLC of morphine (as dansyl derivative, 5 - 80 ng) and 7-aminoflunitrazepam (as fluorescamin derivative, 100 pg - 2.5 ng); fluorescence enhancement was performed by dipping the developed plate (no details) in a solution of Triton X-100 in a 1:7 mixture of chloroform and hexane. Pre-chromatographic reactions on the TLC plate using a commercially available sampler.

J. Chromatogr. Sci. 46 (6), 565-573 (2008). Investigation of selected amino acid standards on cellulose layers using organic-aqueous eluent systems modified with neutral and chaotropic salts: chlorides, iodides, nitrates, thiocyanates, perchlorates, and hexafluorophosphates at low concentrations from 10 to 80 mM in the mobile phase. The effect of salts used as mobile phase modifiers was evaluated by comparison of densitograms, peak symmetry coefficients, and theoretical plate numbers. The efficiency of the investigated chromatographic systems depends primarily on the kind of salt and organic solvent in the mobile phase. The best efficiency was obtained by adding ammonium thiocyanate to the mobile phase which contained acetonitrile as an organic modifier.

J. Chromatogr. A 1218 (52), 9406-9413 (2011). Description of a simple, elegant method for the formation of a continuous stationary phase gradient for use in chromatographic separations, at the example of TLC. Gradient stationary phases were formed on activated HPTLC plates using a newly developed methodology termed “controlled rate infusion”. Reaction of the SiOH groups on the activated HPTLC plates with 3-aminopropyltriethoxysilane in a time dependent fashion by using a programmable syringe pump to control the rate of 3-aminopropyltriethoxysilane infusion into the deposition reservoir. The profile of the gradient was controlled by the infusion rate and visualized by the concentration-dependent color reaction of amino groups and ninhydrin. The advantages of such gradients were shown by optimizing the retention and separation of various components in different mixtures of 1) four weak acids and bases and (2) three widely used over-the-counter drugs. The separation was better on gradient stationary phases than on NP-TLC phases or amino phases. The retention and separation can be controlled by strategically modifying the steepness of the gradient.