Simultaneous determination of glucose and maltose by HPLC using immobilized enzyme reactor and electrochemical detector.

Abstract

Glucose was determined by reacting it with glucose oxidase (GOD) to produce hydrogen peroxide which was then quantified electrochemically. Maltose was converted to glucose with glucoamylase (GAM) for determining subsequently. GOD and GAM were immobilized on controlled-pore silica beads and packed into a short stainless steel column. The effects of pore size of immobilized silica bead surface on the response were studied over the range 100~1000 Å. Maximum responses of glucose and maltose were obtained when pore size of that were 500 Å. The sensitivity of this detection system was nearly the same as that of chemiluminescence and about 5X102-fold that of differential refractive index method. The least detectable amounts of glucose and maltose were 10 ng and 15 ng (S/N = 3), respectively. The use of specific enzymatic reaction and the electrochemical detector made sample pretreatments extremely simple. This system was successfully used to determine glucose and maltose in foods. © 1992, The Japan Society for Analytical Chemistry. All rights reserved.