In order to create a biosensor capable of detecting insulin and other diabetes-related hormones, our group uses a photolithographic process followed by metal film deposition to fabricate a capacitive electrode array [1]. The resulting coplanar interdigitated electrodes (Fig. 1 A) are then functionalized with specific detection antibodies, and the sensor is coupled to the biological sample via a 3D-printed fluid chamber (Fig. 1 B). Additionally, we used a similar metal deposition process and antibody coating method to functionalize quartz prisms to develop surface plasmon resonance (SPR) biosensors capable of multiplexed detection of pancreatic islet secreted hormones [2]
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References:
[1] Castiello, F. R., et al. Phys Chem Chem Phys 21(28): 15787-15797 (2019).
[2] Castiello, F. R.. M. Tabrizian, Anal Chem 90(5): 3132-3139 (2018).