A HIGHLY SELECTIVE AND SENSITIVE ANALYTICAL TECHNIQUE FOR THE DETERMINATION OF ISOMALTULOSE IN PRESENCE OF ITS PROCESS RELATED IMPURITIES BY CAPILLARY ELECTROPHORESIS

Isomaltulose is a rare disaccharide and has drawn the attention of the pharmaceutical and food industry due to its medical applications. In the present investigation, a simple first of its kind capillary electrophoresis (CE) method is developed and validated for the identification and quantification of isomaltulose and its process impurities (trehalulose, sucrose, d-glucose and d-fructose). The analysis is performed at pH: 12.6 using an electrolyte buffer containing 36 mM of Na2HPO4 and 130 mM NaOH. The calibration curves are plotted over a concentration range from 0.25 mM to 3.0 mM with the regression of 0.99 and with detection limits of 0.15 mM, 0.14 mM, 0.13 mM, 0.10 mM and 0.23 mM for isomaltulose, trehalulose, sucrose, d-glucose and d-fructose respectively. Concerning the internal standard, d-trehalose, the relative migration time is 1.32 min for isomaltulose. Better resolution is achieved under optimum conditions of 18 °C temperature, 16 kV capillary voltage and pH of 12.6. The method is found to be specific for the intended purpose and can be used as an orthogonal approach to the current existing United States Pharmacopoeia (USP) High-performance liquid chromatography (HPLC) monograph method.