Optimization of the packing process of microcolumns with the embedded phosphodiester stationary phases

Abstract

The development of new home-made stationary phases involves their packaging procedure and is crucial to obtain satisfactory working parameters. The parameter that illustrates the quality of the packed bed is its efficiency measured as the height equivalent to the theoretical plate. According to the Van Deemetr's equation, it depends on three factors, but only one of them, eddy diffusion, does not depend on the linear flow velocity. Therefore, in order to obtain it as low as possible, it is necessary to focus on a good filling of the column. Among many parameters affecting the quality of column packing, in our work we have focused on the choice of slurry solvent. Novel stationary phases with an embedded phosphodiester group were investigated. The suspensions in 16 solvents and solvent mixtures were studied for their stability, aggregation, sedimentation, and viscosity comparison. The efficiency of the packed microcolumns and its comparison was determined by chromatographic analyses using a polar (thymidine) and a nonpolar compound (naphthalene). The results obtained led to the conclusion that for these stationary phases, the best slurry solvent is the one that aggregates the phase while maintaining stability and having high viscosity.

Beta-Blocker Separation on Phosphodiester Stationary Phases—The Application of Intelligent Peak Deconvolution Analysis

“…Detailed characteristics of these materials are presented in the previous studies [ 25 , 26 ]. Kromasil 100 silica gel (Akzo Nobel, Bohus, Sweden) was used as a support for the stationary phase synthesis.…”

Phosphodiester Stationary Phases as Universal Chromatographic Materials for Separation in RP LC, HILIC, and Pure Aqueous Mobile Phase

“…Each of the stationary phases has a different hydrophobic molecule attached to a phosphodiester group: Diol-P-C10, a decyl chain; Diol-P-C18, an octadecyl chain; Diol-P-benzyl, a benzyl group; and Diol-P-chol, a cholesterol molecule. A detailed procedure for synthesizing and characterizing these materials has been described in previous works [31,32], while the structures are shown in Figure 1.…”