T. Hu et al., Simultaneous determination of glucoamylase activity and glucose in fermentation process based on screen-printed disposable biosensor, ANAL LETTER, 34(1), 2001, pp. 79-90
Screen-printed disposable biosensor with dualcarbon working electrodes and
an Ag/AgCl reference electrode was developed for simultaneous determination
of glucoamylase (GA) activity and glucose. Such determination can be accom
plished in 1 min by immobilizing glucose oxidase (GOD) and GOD/starch onto
different working electrodes. The method was based on electrochemical detec
tion of glucoamylase-catalyzed glucose from the starch layer coupling with
mediator oxidation. Cyclic voltammetry was employed to demonstrate the prin
ciple. Chronoamperometry at +0.4 V versus Ag/AgCl was performed without inc
ubation time. The linear response ranges were up to 20-mmol/l glucose and 1
50-U/ml GA. The method was applied to the measurements of glucose and GA ac
tivity in fungal fermentation process, and exhibited good agreement with th
e reference method.