Control of the polymerization towards porous layer open tubular capillary columns

A novel method for the preparation of monolithic porous layer open tubular (PLOT) columns in fused silica capillaries is presented. In the first experiments, light attenuation by a UV absorbing compound in the polymerization mixture was tested. In another approach, the capillary was first flushed by polymerization mixture followed by a solvent not containing the monomers. However, no useful results were obtained in both cases. When the polymerization mixture at the centre of the capillary was removed with an immiscible liquid (FC-770), a thin layer of polymer monolith was formed. The flushing with FC-770 leaves only a thin film of the polymerization mixture wetting the capillary wall. Subsequent UV initiated polymerization of this film results in PLOT columns with a thin layer of poly(glycidyl methacrylate-coethyleneglycol dimethacrylate) at the wall of a fused silica capillary.