Acta Chrom. 17, 272-291 (2006). TLC on silica gel with 0.1 M glutamic acid – methanol – acetone 1:1:1 has been found to be highly suitable for separation and identification of cationic and non-ionic surfactants. Visualization by use of Draggendorf reagent or iodine vapour. Spectro-photometric determination of tetradecyltrimethylammonium bromide at 670 nm after the spot extraction. The method has been used for identification of tetradecyltrimethylammonium bromide and Triton TX-100 in saline water, river water, and domestic waste water. The effects of sample pH, polarity of the alcohol and nature of the amino acid in the mobile phase, and the presence of alumina, kieselguhr, or cellulose in the silica gel layer have been examined.

J. Liq. Chromatogr. Relat. Technol. 29, 1891-1903 (2006). HPTLC of androsterone, epi-androsterone, dehydro-epi-androsterone, testosterone, stigmasterol, beta-sitosterol, estradiol, hydrocortisone, and cholesterol on RP-18 W with methanol - water, and acetonitrile - water in different composition, with chamber saturation. Detection by spraying with sulfuric acid - methanol 1:9 and heating at 120 °C for 15 min. Densitometric determination of RF values. The aim of the work was to compare the lipophilicity of selected steroids determined by RP-HPTLC on RP-18 W plates using different mobile phases with lipophilicity values estimated by computational methods.

J. Liq. Chromatogr. & Relat. Technol. 29, 2425-2436 (2006). HPTLC and TLC of phenyl isothiocyanate derivatives of biogenic amines (2-phenylethylamine, tyramine, octopamine, dopamine, adrenaline, histamine, tryptamine, putrescine, spermidine, spermine, and calamine) on silica gel and RP-18 in a horizontal chamber saturated for 30 min with hexane - dioxane 1:1; 1:2; and 2:3; hexane - ethanol 1:1, methanol - dioxane 2:1, and hexane - dioxane - toluene 1:1:1. Prechromatographic derivatization with PITC directly on the plate. Detection of NP-TLC plates (silica gel) by spraying with a mixture of sodium azide and starch solution. For RP-TLC sodium azide solution with starch was incorporated into the mobile phase, and then the plates were exposed to iodine vapor. The stability of the resulting white zones on a violet-grey background lastet for several minutes. The results of the detection limits proved to be advantageous to other commonly used detection techniques (UV and iodine chamber).

J. Sep. Sci. 30, 964-970 (2007). Multidimensional planar chromatography of a mixture of five groups of pesticides: (1) diuron, isoproturon, and lenacil; (2) monolinuron, propoksur, carbaryl, and simazine; (3) alachlor and dinoseb; (4) trifluralin, tetradifon, p,p´-DDT, and 4,4´-dibromobenzophenone; (5) hexachlorobenzene. The silica gel plate was developed in the first dimension with ethyl acetate – n-heptane 1:3, and then turned by 90°. Portions of the stationary phase were sequentially removed to ensure that the mobile phase of the following developments reaches only the target spots: (2) chloroform – n-heptane 19:1 (4) acetone – n-heptane 1:59, (3) toluene, and (1) ethyl acetate – dichloromethane 1:9. The plate was dried between 5 and 15 min before each development. Detection under UV light at 254nm.

Pharmazie 61, 747-750 (2006). TLC of phenazopyridine and 4 major metabolites (i. a. p-methoxyaniline) on silica gel with chloroform - methanol mixtures. Also irradiation of phenazopyridine adsorbed on silica gel. The drug was dissolved in methanol and mixed with aqueous slurry of silica gel. TLC plates were prepared and wet plate photolyzed as such with a mercury lamp. The plate appeared as yellow chromatogram, which turned dark yellow within 15 min. The progress of reaction was monitored by Co-TLC of a withdrawn scratch with the starting drug.

Pharmazie 61, 670-672 (2006). TLC of swertisin and 2’’-O-rhamnosylswertisin on silica gel with chloroform - methanol 7:3 and 17:3. Detection under UV light at 254 nm or by spraying with 2 % iron(III) chloride solution in ethanol. The compounds were identified by direct comparison with authentic samples.

J. Chromatogr. A 1116 (1-2), 272-276 (2006). Application of TLC to fractionate well-characterized aquatic humic materials coupled with the novel evaluation of the trihalomethane formation potential of the fractionated materials. HPTLC on silica gel with methanol - ethyl acetate 2:1. Identification of three common fractions based on retention factor (Rf) in all substances examined.

Biomed. Chromatogr. 21 (1), 94-100 (2006). Presentation of a post TLC developing technique to detect substances which can inhibit tyrosinase activity. The TLC plate is sprayed with tyrosinase and l-tyrosine solutions successively. A positive result is detected as white zone against a brownish-purple background. The method is suitable as a quick screening procedure for tyrosinase inhibitor detection, and as a guiding procedure for the isolation of tyrosinase inhibitors from mixtures or natural product extracts.