Modeling Pore Size Distribution in Cellulose Rolled Stationary Phases

Rolled stationary phases are fabrics (i.e., nonparticulate phases) that rapidly separate proteins from salts on the basis of size exclusion. Pore size and pore size distributions in the stationary phase determine how different size molecules distribute between the stationary and mobile phases in liquid chromatography columns. The potential for size exclusion chromatography by fabrics is not initially obvious because their interlaced structures are atypical for size exclusion supports. A simple logistic model fits the pore size distribution of a rolled stationary phase when pore sizes were measured using PEG, Dextran, D2O, glucose, and NaC1 probes. When the fabric is treated with cellulase enzymes, the water-accessible pores uniformly decrease and peak retention is lower. The logistic function model captures this result and enables comparison of pore size distribution curves between enzyme-treated and untreated fabrics in rolled stationary phase columns.