Prabuddha is a Research Scientist at the Chemical Imaging and Structural Laboratories (CISL), Beckman Institute of Advanced Science and Technology at the University of Illinois at Urbana Champaign. He is interested in developing novel Raman and Infrared techniques that can be implemented in various materials and biological applications with Prof. Rohit Bhargava. Presently his research interest lies around but not limited to novel tunable luminescent Carbon nanoparticles for cancer diagnostics and therapy, semiconductor nanocrystals for infrared imaging, quantitative estimation of drug uptake in cells and developing Raman instrumentation to estimate the nutrition content in various agricultural products. Prabuddha also works in close collaboration with companies like Chevron Philips Chemical company and United Soybean Board.
Prior to this, Prabuddha, for a brief period, was a post doctoral research associate with Prof. William L. Wilson at the Materials and Research Laboratories at the UIUC. Here he designed transient absorption microscope for measuring semiconducting single walled carbon nanotubes and an infrared tool to selectively ablate metallic carbon nanotubes. His first poct doctoral research experience was with with Prof. Dana Dlott in the Department of Chemistry at the University of Illinois at Urbana Champaign. In this group his primary focus was to understand the chemistry at the interfaces as often they are different from the bulk and are relatively unknown. Here he developed spectroscopic techniques to probe these unknown chemistries at the interfaces. These interfacial chemistries have a lot of practical applications as they play a crucial role in energy storage mechanisms in fuel cells, rechargeable batteries, semiconductors, nanotechnology etc. Typically, the group used various electrochemical techniques to initiate chemical reactions on the surfaces of electrodes and then measured them with surface sensitive spectroscopy techniques.
Developing a spectroscopic probe that is sensitive and selective to the species present at the surface/interface is challenging. Unlike other infrared spectroscopic techniques that probe the bulk media, vibrational sum frequency generation (SFG) spectroscopy selectively probes the surface. This is because SFG measures the second order polarization that originates from the surface/interfaces or wherever the center of symmetry is broken. Coupled with electrochemical techniques such as cyclic voltammetry (CV) where the voltage of the electrodes is varied, the SFG spectrum of interfacial reacting species and their products on these electrodes can be measured and also the reactions can be monitored real time.
Prabuddha’s journey with IR spectroscopy began under the tutelage of Prof. Martin Zanni at University of Wisconsin-Madison where he completed his Ph.D. Prabuddha investigated membrane bound proteins with heterodyned Two Dimensional Infrared Spectroscopy (2DIR). 2DIR, unlike SFG probes the bulk molecules. Time domain 2DIR experiments have the ability to measure accurate lineshapes of a vibrational mode that has the information about the environmental fluctuations around that mode. Aided with isotope labeling they able to isolate various vibrational modes (amide I modes) of the membrane protein spectroscopically and measured the lineshapes of each of them. These experiments were the first of its kind in the 2DIR spectroscopy field and their studies revealed a detailed description (both qualitative and quantitative) of the various environments in a trans-membrane protein.