Packed capillary liquid chromatographic columns with conical end

Packed capillary liquid chromatographic columns with conical end were prepared and evaluated. It was found that the column efficiency was 30% similar to 50% higher than that of the columns with conventional end, for columns of 0.53 mm I.D.. The Van Deemter curve of the novel shape column was also improved substantially, particularly in the high flow rate region. The difference for columns of smaller diameter (0.32mm and 0.25mm I.D.) was less because of smaller dead volume and less disturbance of now profile at the column end