Retention reproducibility of basic drugs in high-performance liquid chromatography on a silica column with a methanol—high-pH buffer eluent

Abstract Basic drugs can be separated by high-performance liquid chromatography on silica using a methanol-aqueous pH-10 buffer eluent prepared from 3-(cyclohexylamino)-1-propanesulphonic acid and sodium 3-(cyclohexylamino)-2-hydroxyl-1-propanesulphonate. The buffer could be reproducibly prepared. The effects of small changes in the buffer and eluent composition and in the operating temperature on the relative retentions of the different groups of drugs were determined.