Comparison of high-performance capillary electrophoresis and liquid chromatography on analysis of zinc 5-aminosalicylate dihydrate and related materials.

Separation and determination of zinc 5-aminosalicylate dihydrate (ZASA) and related materials by high-performance capillary electrophoresis (HPCE) and liquid chromatography (HPLC) have been studied systematically. The R.S.D. of peak time and area and detection limits of materials were lower in HPLC compared to HPCE. HPCE and HPLC were used for determining ZASA and related materials in crude and treated ZASA using acid and heat, and similar results with both techniques showed the principal impurities in the crude ZASA were 5-aminosalicylic acid (ASA) and salicylic acid (SA), the compounds from ZASA decomposing under conditions of acid and heat were ASA, p-aminophenol and 5-benzeneazosalicylic acid.