Integration of carbon nanotubes to three-dimensional C-MEMS for glucose sensors

• Glucose sensor with C-MEMS/carbon nanotubes integrated electrode was fabricated.
• The modification of carbon nanotubes improves the sensitivity about 50 times.
• The response time is less than 10 s with linear range from 5 to 80 mM.

The amperometric glucose biosensor utilizing glucose oxidase immobilized in polymerized polypyrrole film was constructed on multi-walled carbon nanotube (CNT) modified C-MEMS electrode. Dense coverage of CNTs was successfully integrated on the surface of the C-MEMS, which greatly increased the effective electro-active surface area thus resulting in higher loading of enzyme. Electrochemical studies reveal that the C-MEMS/CNT based glucose sensor displays linear response for glucose concentrations from 5 to 80 mM with a sensitivity of 97.3 mA M−1 cm−2 with the response time less than 10 s. The detecting sensitivity was proved to be increased more than 50 times compared with 1.7 mA M−1 cm−2 for the blank C-MEMS one.