Open tubular capillary electrokinetic chromatography in etched fused-silica tubes

This review describes an open tubular approach to capillary electrochromatography (OTCEC) that first etches the inner surface of the fused-silica tube using ammonium hydrogen diflouride. This process can increase the inner surface area significantly. The new surface is then chemically modified to attach a bonded stationary phase using a silanization/hydrosilation reaction process. The surfaces are characterized spectroscopically by diffuse reflectance infrared Fourier transform and by electroosmotic flow measurements. Applications of OTCEC columns with C18, diol and chiral stationary phases are described.