A novel electrochemiluminescence glucose biosensor based on alcohol-free mesoporous molecular sieve silica modified electrode

In this study, a thin-film glucose electrochemiluminescence (ECL) biosensor was developed. Ru(bpy)32+ was doped in alcohol-free low-volume shrinkage mesoporous silica sol–gel with PEG-400 as the template, and glucose dehydrogenase (GDH) was immobilized in polymer Resydrol. NADH, which is produced by the reaction of co-enzyme NAD+ and glucose catalyzed by glucose dehydrogenase, reacts with immobilized Ru(bpy)32+ to generate ECL emission. Among the three types of design including two-layer, mixed and sandwich configuration, the sandwich configuration showed the best sensitivity with the calibration range of 25–2000 μM and the limit of detection of 0.5 μM in a flow injection analysis of glucose. The alcohol-free mesoporous sol–gel and the sandwich design made the biosensor potentially applicable in flow-injection analysis of samples.