(2az) Understanding Nanomaterials for Biosensors and Catalysts

The manipulation of the material nanostructure is an important research area in the field of material science. Nanoscale materials exhibit high surface to volume ratio than bulk materials which leads to their improved performance and makes them a good candidate for the creation of effective catalysts. Such materials can be further used for developing biosensors, point of care (POC) devices, and mimicking natural enzymes’ catalytic activity. The nanomaterials that can mimic an enzyme's catalytic activities are called nanozymes. Therefore, my research interest lies at the intersection of nanoscience and biosensors. In my Ph.D. thesis, I developed the first reusable nanozyme with peroxidase-like activity for colorimetric detection of uric acid.¹ The nanozyme exhibited high surface energy, which was further enhanced with NH₃ plasma modification to closely mimic the natural enzyme’s (peroxidase) catalytic activity.² Additionally, these nanostructured materials were also used to develop an enzymatic electrochemical sensor for food freshness (through xanthene detection) monitoring.³ Finally, I have also worked towards developing sandwiched nanomaterials for piezoresisitve based pressure (100 Pa to 3500 Pa) sensing.

My future research would typically aim towards addressing the design spaces for reusable nanostructured materials, sustainable process techniques for nanostructured materials’ synthesis, and their application to healthcare, environment, and energy. I plan to explore different methods for developing nanostructured materials with controlled features using electrochemical and physical vapor deposition techniques. The primary goal would focus on three main thrusts using the nanostructured materials: (1) Nanozymes to mimic oxidase, peroxidase, catalase, and superoxidase enzymes’ catalytic activity for developing affordable point-of-care devices, (2) theoretical studies for understanding the nanozymes’ catalyst activities at the atomic scale, (3) sandwiched nanostructured materials on flexible substrates for developing piezo-resistive based pressure (1-10 kPa) sensors. These thrusts will aim to address the fundamental questions for two major research directions – utilizing the artificial enzymes as a substitute under uncontrolled operating conditions of pH and temperature, and the development of reusable nanostructured material enabled stimuli-responsive devices.

Teaching interests

Based on my teaching assistance experience during my Ph.D, I am interested in teaching courses related to electrochemistry, thermodynamics, analytical chemistry, and chemical reaction engineering. I am also interested in proposing new chemical engineering-based elective courses at the undergraduate or graduate level, whose focus would be on nanostructured materials fabrication and their applications. I further look forward in contributing towards STEM diversity through outreach programs that would focus on training high school students and creating research opportunities for underrepresented students.

References

[1] A. Tripathi, K. D. Harris, A. L. Elias (2020), Peroxidase-Like Behavior of Ni Thin films Deposited by Glancing Angle Deposition for Enzyme-free Uric Acid Sensing, ACS Omega, April, 9123–9130.

[2] A. Tripathi, K. D. Harris, A. L. Elias (2021), High Surface Area Nitrogen-functionalized Ni Nanozymes for Efficient Peroxidase-like Catalytic Activity, PLoS One, October, e0257777.

[3] A. Tripathi, A. L. Elias, A. B. Jemere, K. D. Harris (2022), Amperometric Determination of Xanthine Using Nanostructured NiO Electrodes Loaded with Xanthine Oxidase, ACS Food Science & Technology, July, in-press.