Recent Studies of the Fused Silica Surface in Capillary Chromatography

By using gas chromatographic intermediate surface testing to study the surface properties of fused silica capillary tubing, the reversible adsorption of aldehydes and ketones on the fused silica surface has been observed for the first time. It is shown that this interaction can arise from the preferential interaction of carbonyl functional groups at bonded silanol sites on the surface. It is further shown that simple test mixtures containing aldehydes or ketones can be used to probe the concentration of water and bonded silanols on the surface and thus to evaluate capillary manufacturing processes and thermal and chemical surface treatments.