High Frequency Studies of the Interaction of Micro Nanoparticles with Proteins and Pathogens

Abstract

Characterization of biomolecules plays a crucial role in understanding the biological function, cell-ligand interaction, structural and functional changes under various physicochemical conditions which can help in various fields not limited to clinical diagnosis, food quality monitoring, agriculture, and pharmacological field. This thesis presents the characterization of protein and pathogens along with their interaction with morphologically different micro-nano particles (MNPs). The dielectric characterization of protein under various perturbing conditions like adding MNPs, adding a denaturing agent, and applying environmental stress are performed through the microwave resonant technique. In addition to the dielectric characterization, theoretical modeling is also formulated for calculating other important physical parameters like dipole moment, mechanical frequency, polarization current density, and enthalpy which gives a new view of understanding the nano-bio interaction. Furthermore, results are further validated experimentally by microwave spectroscopy, electrophoretic technique, UV VIS spectroscopy, and differential scanning calorimetry. newlineFurthermore, the characterization of bacteria along with MNPs is performed through electrophoretic technique and agar plating. To study the bacterial survivability, RC circuit analysis on the time-varying current signal (measured from a dynamic light scattering instrument) is performed to calculate various physical parameters such as capacitance, resistance, and energy (required for membrane destruction) of the bacterial solution. In addition to the characterization of bacteria, the MATLAB GUI is developed for understanding the quorum sensing of bacteria. newlineAdditional works carried out during the doctoral work include a study of DC field (1 V -100 V) on phantom of bacteria using an mm-sized device through CST simulations, time-dependent study of dielectric characterization, and Lagrangian analysis of both protein and pathogen using truncated waveguide cavity, and high-frequency characterization of the other biological samples using patch antenna along with additional capability like tuning in resonant frequency. newline newline