Kosuri Vikranth Varma supervised by Dr. Anshu Sarje received his Master of Science in  Electronics and Communication Engineering (ECE). Here’s a summary of his research work on Design and Fabrication of Metal Oxide Nanoparticle-Based Sensors for Gas Sensing and Disease Diagnosis Applications:

This thesis investigates the design, fabrication, and characterization of zinc oxide (ZnO)-based nanoparticle sensors, focusing on applications in gas sensing and microorganism detection. The research addresses critical challenges in environmental monitoring and medical diagnostics by introducing innovative, cost-effective, and portable sensor solutions. A microheater design optimized for precise thermal control was developed using joule and induction heating techniques, enabling reliable operation in microfluidic and biochemical systems. ZnO nanostructures, particularly nanorods, were explored for their unique properties, including high surface-to-volume ratios, biocompatibility, and thermal stability. A ZnO nanorod-based biosensor integrated with an electrochemical impedance spectroscopy (EIS) circuit demonstrated high sensitivity in detecting yeast concentrations, showcasing potential applications in biomedical diagnostics. To further enhance bio-sensing performance, functionalization of ZnO nanorods with Concanavalin A (ConA) protein was implemented, resulting in improved selectivity and sensitivity. Additionally, the development of flexible ZnO-based CO2 gas sensors on PDMS substrates highlighted their effectiveness in real-time gas detection for industrial and environmental safety. The integration of microheaters with gas sensors significantly improved their sensitivity and response by optimizing temperature conditions. Microheaters were utilized to enhance the chemical reactivity of ZnO nanorods, ensuring faster and more accurate gas detection, especially for CO2. The precise thermal control offered by the microheaters allowed sensors to operate efficiently in varying environmental conditions, making them highly suitable for both wearable applications and harsh industrial environments. The results underscore the scalability and efficacy of ZnO-based sensors, balancing affordability with performance. The proposed systems address limitations in existing technologies, such as limited portability and low specificity, and emphasize their suitability for IoT-enabled real-time monitoring. Future research can expand on these findings by exploring additional gas and pathogen detection capabilities, integrating advanced machine learning for data analytics, and enhancing the durability and energy efficiency of flexible and wearable sensors. These advancements will contribute to smarter, more sustainable monitoring systems across diverse domains.

June 2025