Transient method for proposing the mechanisms of reactions over immobilized enzymes.
The transient response method is introduced to elucidate the mechanism of reaction over immobilized enzyme. Glucose oxidation over the glucose oxidase that was immobilized on ion-exchange resin using glutaraldehyde as a linking agent is selected as an example here. The transient responses of a fixed-bed reactor to step increases and decreases in glucose, oxygen, and gluconolactone feed concentrations have been monitored and interpreted. From some responses, we have found that gluconolactone is formed in the reaction of glucose with adsorbed oxygen, while hydrogen peroxide is formed in the reaction of oxygen with adsorbed glucose. Combining all information from interpreting the responses with the literature, a mechanistic picture can be obtained as follows: E(ox)+G-->E(red)GL E(red)GL-->E(red)+GL E(red)+O(2)-->E(ox)H(2)O(2) E(ox)H(2)O(2)-->E(ox)+H(2)O(2)
Wu
J Y
JY
Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan, 70101, R.O.C.
Weng
H S
HS