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This paper presents a review of the literature concerning development of the stationary phases for thin-layer chromatography (TLC) in the last ten years. The silica gel remains the most important adsorbent for TLC separation. The kinetic properties of the silica-gel thin layer and the new TLC plates have been presented. Other materials used as stationary phase were alumina, zirconium oxide, Florisil, and ion-exchanger. Chemically new bonded stationary phase development is also discussed. The improvement of the separations of some organic mixtures by impregnation of silica gel, cellulose, or polyamide plates (with transition metal ions and silver salts) and their applications is presented. The impregnation of the thin layer with organic stationary phase and inclusion complexes is another method used for the enhancement of the separation efficiences. Another modality to improve the selectivity in TLC using ion-pairing as reagent of impregnation is described as well. The actual state of chiral separation by TLC is discussed with concrete references to recent advances in chiral stationary phases. The use of nonpolar chemically bonded stationary phases impregnated with transitional metal ions is presented as chiral stationary phases. The cellulose, modified cellulose, chitin, chitosan, and their derivatives are presented and their potential for the analysis of the racemates is discussed. The cyclodextrines and macrocyclic antibiotics were used with very good results for enantiomeric separation by TLC. A new separation approach with molecular imprinting polymers was reported as a chiral stationary phase in TLC. The examples provide a wide range of structural types that can be readily resolved enantiomerically by TLC.

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A new, sensitive, high throughput liquid chromatography coupled with mass spectrometry (LC-MS=MS) method for quantification of trans-andcisresveratrol in wine samples was elaborated. During method development the influence of multiple factors on the ionization efficiency of resveratrol was studied. These parameters included ion source (APCI and ESI, both being operated in positive and negative ionization mode), percentage of aqueous and organic phase, type of organic solvent, and concentration of additives. The optimum conditions were as follows: a mobile phase consisting of a mixture of 1 mM ammonium acetate=acetonitrile (73=27, v=v) with a flow rate of 1 mL=min, MS=MS detection with an APCI interface, operated in negative ionization mode. The monitored ion transition was m=z 227!184.7. Calibration curves were generated for both isomers of resveratrol in the range of 10.47-837.86 ng=mL (trans isomer) and 9.12 À 730.14 ng=mL (cis isomer), respectively. The developed method has been successfully applied to the analysis and comparison of trans-and cis-resveratrol content of 20 different Romanian wine samples.