Team members: Abhinav Agarwal, Albert Agural, Manuel Monge, in collaboration with Caltech Nanofabrication Lab
Miniaturization of implantable biosensors for continuous, in vivo monitoring of clinically relevant analytes is an important step toward viability of such devices. While wireless power delivery via on-chip antennas promises miniaturization and realization of minimally invasive devices, it can only support low levels of power consumption. This is due to the significant tissue absorption at high frequencies, small size of the chip and quality factor of on-chip inductors. Therefore, reducing the power consumption of the sensor while maintaining high sensitivity and dynamic range is crucial.
We propose an ultra-low power potentiostat that achieves sensitivity and meets the dynamic range requirements of in-vivo amperometric sensing. We present a 1.2×1.2mm2 fully implantable device with integrated electrodes, wireless power harvesting and data communication. The electrodes are post-processed and functionalized, and performance of the implant is verified via in-vitro measurements in hydrogen peroxide. The system consumes 4µW of power, and can accurately detect input currents ranging from 100pA to 350nA with a sensitivity of 100pA over the full range.
Related News and Publications
Abhinav Agarwal, Albert Gural, Manuel Monge, Dvin Adalian, Samson Chen, Axel Scherer, Azita Emami, “A 4μW, ADPLL-based implantable amperometric biosensor in 65nm CMOS ,” IEEE Symposium on VLSI Circuits, June 2017
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MICS Lab’s collaborative work with Caltech Nanofabrication Lab on micro-scale implantable devices for diabetes management featured on the cover page of the Heritage Provider Network’s quarterly magazine.