The performance of the O2 scavenger was tested on a glucose biosensor based on GOx. The experiments were first conducted in a standard 3-electrode cell with a glassy carbon electrode (GCE) as working electrode to demonstrate the proof-of-concept for glucose sensing. In a first sensing configuration, the redox mediator Fc(MeOH)2 and GOx were freely diffusing in solution. In a second configuration, GOx was immobilized on the electrode in the Os-complex modified polymer . In the latter case, the electrode was modified with 200 μg cm -2 of polymer (50%), GOx (40%) and crosslinker (10%). This ratio and loading led to the maximum catalytic currents for glucose oxidation (Figure ).