The separation conditions of several drugs by reversed-phase ion pair and ion suppression HPLC were described, respectively. Their chromatographic behaviour on the C18 columns was studied.

Based on the analysis of the separation properties of existing flotation columns and their defects, this paper expounds the structural characteristics and test results of a modified flotation column.

The separation of methanol, acetaldehyde and ethyl acetate in the standard liquor sample on the monolithic column is much more convenient than that on PEG-20M columns.