Design and Development of A CMOS Integrated Multimodal Sensor System with Carbon Nano-electrodes for Biosensor Applications

This dissertation outlines the design and development of a CMOS integrated multimodal sensor system that leverages advanced carbon nanoelectrodes for innovative biosensor applications. The proposed system incorporates five synergistic sensors: temperature, impedance, pH, electrochemical, and optical sensors, which collectively enable the comprehensive analysis of biological phenomena. By integrating these modalities into a lab-on-CMOS platform, the system aims to capture in situ real-time physiological data from live biological cells, specifically genetically enhanced autobioluminescent glioblastoma cells.

A key innovation of this research is the fabrication of biocompatible nanoelectrodes using a novel approach that combines 3D printed polymer structures with Ti/Pt alloy metal electrodes. Polymer electrodes undergo a pyrolysis process to convert them into carbonized nanoelectrodes, optimizing their electrical properties to enhance interaction with biological samples. This design not only facilitates the precise monitoring of cellular behavior in response to various stimuli, but also enhances the sensitivity and specificity of the biosensing platform.

This novel design is the first example of a multimodal system with five sensors in one integrated chip in CMOS technology. The system also includes carbonized polymer nanoelectrodes on top metal pads. The technique of pyrolysis of polymers in CMOS-compatible temperatures is also relatively new, and this technique has been incorporated here in CMOS technology for the first time. The integration of multimodal sensing capabilities allows for a holistic understanding of cellular dynamics and biochemical interactions, addressing current limitations in biosensor technology. This research aims to contribute to the fields of biomedical engineering and nanotechnology by providing a robust framework for the real-time assessment of cellular responses, with potential applications in cancer research, drug development, and personalized medicine. Ultimately, this dissertation will advance the state-of-the-art in biosensing technologies by establishing a powerful tool for investigating complex biological systems.