| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1199880 | Journal of Chromatography A | 2013 | 8 Pages |
•Novel thick film silica open tubular capillaries were synthesized using a sol–gel method.•Resulting columns showed approx. 400-fold higher permeability in comparison to monolithic and particle packed reference capillaries.•Column efficiency gain compared to reference column was evaluated in terms of a kinetic plot limitation comparison.
It is well-known that the open tubular column design basically can offer very high plate numbers. Experimental realization has however not kept pace with theoretical considerations, lacking efficient methods for the deposition of a thick film porous layer within a microbore capillary. A previously published sol–gel synthesis method was extended from 20 μm to 10 μm inner diameter fused silica capillaries and the resulting columns were compared to a monolithic reference capillary in terms of kinetic performance at pressure maximum. Column permeability was investigated and pressure/flow-diagrams were obtained with a 400-fold permeability gain for the open tubes. Structural characterizations regarding layer thickness and surface porosity were carried out and displayed via scanning electron microscopy and nitrogen sorption analysis. Chromatographic results in normal phase mode at elevated mobile phase flow rate reveal the intrinsic performance potential of this column format when it comes to kinetic performance limitation plots, which were constructed for all columns prepared and compared to the monolithic silica reference capillary.
