Preparation of short glass microbore columns for liquid chromatography and their properties

Abstract

The preparation is described of thick-walled glass columns, inner diameter 0.5 mm and outer diameter 4.5 mm, packed with Separon SI C 18 (dp = 6 and 10 μm) from suspension under pressures of 20-35 MPa in the presence of an ionogenic detergent; the column length ranged from 5 to 30 cm. The minimum value of the height equivalent to a theoretical plate was Hmin = 2.8 - 3.3dp. The effect of the extra-column contributions to the dispersion on the slope of the linear part of the dependence of the height equivalent to a theoretical plate on the mobile phase velocity was examined and found to become significant at higher velocities, thereby imposing limitations on the shortening of the time of analysis.