| Abstract: | The reaction between glucose and methylene blue, catalyzed by glucose oxidase (GOD)was analysed calorimetrically. The amount of heat produced under saturating methylene blue concentrations ( > 10?2 mol/1)was measured with glucose concentration and time as parameters (kinetic procedure) Kinetic constants (pseudo one substrate kinetics) were derived from the experimental data: KM(glucose)= 1.18 × 10?3 mol/l and Vmax = 0.085 J/mg GOD min (3.89 · 10?6 mol/mg GOD min) Comparison of caloric with optical measurements gave an enthalpy of reaction of 22.52 kJ/mol. Considering the observed substrate inhibition, glucose determinations are possible up to glucose concentrations of 0.1 mol/l. |
