Selection of comparison criteria and experimental conditions to evaluate the kinetic performance of monolithic and packed-bed columns.
The present study concerns the problem of finding appropriate experimental conditions and comparison criteria to assess the kinetic performance of LC supports with different sizes or morphologies. A general procedure, based on evaluating each support for its own optimal mobile-phase composition, is proposed. The practical elaboration of the procedure is illustrated using the specific case of a capillary LC separation of a series of polycyclic aromatic test compounds employing silica-monolith capillary columns and capillary columns packed with 6-microm porous particles. To compare the systems for their ability to yield the fastest critical-pair separation, plate-height measurements are transformed into an effective plate number kinetic plot, i.e., a plot of the extrapolated retention time divided by the square of the extrapolated effective plate number (t(R)/N(eff)(2)) versus N(eff). This type of data representation provides a direct and universal basis to compare the kinetic performance of different LC supports and it corrects for differences in retention strength arising from different phase ratios.
Eeltink
Sebastiaan
S
Polymer-Analysis Group, Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV, Amsterdam, The Netherlands.
Gzil
Piotr
P
Kok
Wim Th
WT
Schoenmakers
Peter J
PJ
Desmet
Gert
G
D002853:Chromatography, Liquid / Q000295:instrumentation* / Q000379:methods; D007700:Kinetics; D010316:Particle Size; D016062:Porosity