Integration of interstitial fluid extraction and glucose detection in one device for wearable non-invasive blood glucose sensors

Wearable non-invasive glucose sensors that can provide human a painless and portable means to monitor their blood glucose and manage their health condition draw great attentions, recently. Non-invasive human glucose sensors by detecting glucose in interstitial fluid (ISF) extracted through a reverse iontophoresis (RI) approach have been widely investigated, but the current challenges are their complex structure and instability for continuous monitor. Herein, we demonstrate a simple two-electrode non-invasive blood glucose sensor, which is fabricated by using graphene/carbon nanotubes/glucose oxidase composite textile and graphene/carbon nanotube/silver/silver chloride composite textile as the working electrode and counter electrode, respectively. By using one single device, extraction of ISF through RI process is firstly conducted by loading a certain electric current between two electrodes, then the glucose concentration in the ISF is detected through an amperometric approach by using the same two electrodes. The feasibility of these non-invasive glucose sensors is validated on porcine skin, nude mice and human. The blood glucose concentration calculated according to the response currents of the two-electrode sensors is highly consistent with that measured by commercial glucose meter. Furthermore, the used textile-like electrodes provide the non-invasive blood glucose sensors with excellent flexible and wearable properties, which make them promising to be integrated with other electronic units for monitor and management of human health.

Automated summary

The article introduces a simple two-electrode non-invasive blood glucose sensor, which extracts glucose concentration in ISF through RI process for blood glucose monitoring and validates its feasibility on different animals and human subjects.