Microchip based electrochemical-piezoelectric integrated multi-mode sensing system for continuous glucose monitoring

We presented a MEMS multi-mode sensing system by integrating electrochemical working electrode and solid-mounted thin-film piezoelectric resonator (SMR) on a single micro-sized chip, which is capable of detecting three sensing modes of electrochemistry, gravimetry and viscometry. As a model test sample, glucose concentration was successfully monitored using this integrated sensor. The electrochemical sensor amperometrically detected glucose concentration change, and SMR tracked the concentration variation through impedance response to viscosity. Optimized number of single-walled carbon nanotubes (SWCNTs) - poly (dimethyldiallylammonium chloride) (PDDA) / glucose oxidase (GOD) modification layers was also determined with the help of SMR by monitoring the mass-sensitive frequency shift. SMR proved to be a suitable support for chip-integrated electrochemical sensor for glucose detection. This integrated chip sensor can be conveniently fabricated with high throughput, shows significant potential for chemical and biological sensing applications.