A More Comfortable Approach to Continuous Glucose Monitoring
Based on previous research literature, the AIT team understood that the microneedle solution they envisioned would require three components:
- The microneedles themselves,
- Metallization to enable the definition of the electrodes for the electrochemical measurements,
- A biofunctionalization layer—a surface modification enabling the glucose detection with direct electron transfer to the electrode.
All of this would be placed on a flexible foil that, when applied to the skin like a patch, would monitor glucose level in real time in the dermal interstitial fluid, just below the skin surface without reaching nerves or blood vessels.
AIT quickly determined that a conventional metallization process would suffice, but the biofunctionalization and microneedles would require a novel approach. Traditional finger-prick glucometers use glucose oxidase, which enables the generation of a signal in the presence of glucose in the blood sample. However, in order to transport the electronic signal to the electrode, the glucometers also require partially toxic mediators, which are a limiting factor for minimally invasive applications.
To solve that problem, AIT partnered with DirectSens, a pioneer in third-generation biosensors. The DirectSens technology provided the safe, direct electron transfer enzyme biofunctionalization required for the novel surface modification and microneedles AIT envisioned. This allowed the team to lower the voltage required to operate the NUMBAT biosensors, therefore reducing interferences and enabling longer-life performance.