Overpressure layer chromatography OPLC

These workers used binary solvent systems over a range of mole fractions to determine, for each solute, the constants a and b of equation (8.2). For methyl and phenacyl esters, TLC was used, while overpressured layer chromatography (OPLC) was used for dansyl amino acids. Nurok and co-workers (11) also evaluated how the quality of a simulated separation varies with changing solvent strength by using the inverse distance function (IDF) or planar response function (PRF), as follows ... 

The 2D chromatograms reveal additional components of the natural mixtures. They also give a map of the essential oil, which is helpful in the identification of the components by the position and the characteristic colours of the derivatives on the plate. A further, considerable improvement in the separation performance can be obtained by using overpressured layer chromatography (OPLC). Harmala et al. (70) used 2D OPLC for the separation of coumarins from the genus Angelica. Figure 10.15 shows the one-dimensional (a) and two-dimensional (b) OPLC separations of 16 coumarins. 

Overpressure layer chromatography (OPLC) can be employed as a cleanup method for HPLC, or used for prefractionation. OPLC-HPLC coupling has been described by ref. [1003],... 

The term overpressured layer chromatography (OPLC) was originally introduced by Tyihak et al. [5] in... 

Many of the inconveniences of TLC are avoided in overpressured layer chromatography (OPLC), which... 

Nyiredy, Sz., C. A. J. Erdelmeier, and O. Sticher, in Proc. Int. Symp. TLC with Special Emphasis on Overpressured Layer Chromatography (OPLC) (E. Tyihak, ed.), LABOR MIM, Budapest, 1986, p. 222. Nyiredy, Sz., S. Y. Meszaros, K. Dallenbach-Toelke, K. Nyiredy-Mikita, and O. Sticher, /. High Resolut Chromatogr Chromatogr. Commun. 10 352 (1987). Rozylo, T. K., R. Siembida, and E. Tyihak, Biomed. Chromatogr 13 1 (1999). 

Several mobile-phase optimization strategies in TLC are based on the use of isoeluotropic solvents (i.e., solvent mixmres of identical strengths but different selectivities). Selecting mobile phase will be achieved based on the eluotropic series (Figs. 1 and 2). These considerations are very general. The selection and optimization of one system of eluent is a more complex problem and must be discussed for each particular system. For example, the separation of 13 phenylurea and s-triazine herbicides was performed by overpressured layer chromatography (OPLC) with a binary... 

Many of the inconveniences of TLC are avoided in overpressured layer chromatography (OPLC), which is a logical extension of the theory and practice developed in HPLC which can now be used in the field of planar liquid chromatography. This extension offers some exceptional... 

Nyiredy, Sz. Erdelmeier, C.A.J. Sticher, O. Proc. Int. Symp. TLC with Special Emphasis on Overpressured Layer Chromatography (OPLC) Tyihak, E., Ed. LABOR MIM Budapest, 1986 222. 

Nyiredy, Sz., Meszaros, S. Y., Dallenbach-Tolke, K., Nyiredy-Mikita, K., and Sticher, O. (1987). The disturbing zone in overpressure layer chromatography (OPLC). J. High Resolut. Chromatogr. Common. 10 352—356. 

Forced-flow planar chromatography (FFPC) with the use of external pressure (overpressured layer chromatography, OPLC) or centrifugal force (rotation planar chromatography, RPC) can be used for off-line or on-line PLC (Mincsovics et al., 1988 Nyiredy, 1990). In off-line FFPC, the procedures after development... 

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