Chromatography overpressurization

Postaire, E., Sarbach, C., Delvordre, P., and Regnault, C. (1990). A new method of derivat-ization in planar chromatography overpressure derivatization. J. Planar Chromatogr.—Mod. TLC 3 247-250. 

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],... 

OPLC Overpressured layer chromatography PID (1) Photon-induced dissociation ... 

The PRISMA model274 and factorial experimental design were applied in the development of a one-dimensional overpressured layered chromatography separation method for the anti-neoplastic bis-indole alkaloids vincristine (102a), vinblastine (102b) and some derivatives275. 

L. Botz, Sz. Nyiredy and O. Sticher, Applicability of long distance overpressured layer chromatography , J. Planar Chromatogr. 4 115-122 (1991). 

K. Kovacs-Hadady, Study of the retention behavior of barbiturates by overpressured layer chromatography using silica gel... 

Z. Witkiewics and J. Bladek, Overpressured thin-layer chromatography, J. Chromatogr., 373 111 (1986). 

Pelander, A., Ojanpera, I., and Vuori, E. 1998. Analysis of cyanobacterial hepatotoxins by overpressured layer chromatography. Joitmai of Planar Chromatography. 11 365-369. 

In the case of circular development, the simplest one-point supply may be used. The samples are spotted all around a circle the mobile phase supply is in the centre. Equipment based on overpressured (forced-flow) chromatography has also been introduced commercially, such as the Chrompres 10. Chrompres 25 and Chrompres 50 instruments of Labor MIM (today Laberte), Budapest, Flungary. as well as the Model P-OPLC BS 50 of the Engineering Company Ltd. (Budapest, Hungary). 

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