Viswanath (Vishy) Gorti
BME PhD Defense Presentation

Date: 2025-08-29
Time: 10:00am
Location / Meeting Link: EBB CHOA Seminar Room

Committee Members:
Francisco E. Robles, PhD (Advisor); Shu Jia, PhD; Erin Buckley, PhD; Wilbur Lam, MD/PhD; Waitman Aumann, MD


Title: Deep-ultraviolet microscopy for point-of-care diagnostics and multiscale cell characterization

Abstract:
Deep-ultraviolet (UV) microscopy is a powerful label-free imaging modality that enables high-resolution visualization of biological structures by leveraging the intrinsic absorption of biomolecules in the UV spectrum (~200-400 nm). The use of UV light in microscopy has been historically limited due to phototoxicity concerns, but recent advances in UV imaging hardware have inspired the re-emergence of the optical technique for various live cell imaging applications, including quantitative biomolecular mass mapping, hematological analysis, and histopathology. This dissertation presents the development, validation, and application of novel deep-UV microscopy systems to expand its utility for both point-of-care diagnostics and fundamental biological research. Aim 1 of this work focuses on the development of compact, low-cost UV microscopy systems for point-of-care hematology. These devices demonstrate high-resolution imaging of blood smears and bone marrow aspirates, enabling cell classification and adequacy assessment without the need for extensive sample preparation or biochemical stains. Aim 2 establishes deep-UV microscopy as a powerful tool for live-cell imaging by quantifying UV-induced phototoxicity and leveraging dynamic intracellular activity for cell phenotyping. These studies demonstrate the ability to distinguish immune cell subtypes and characterize cancer cell lines of varying malignancy, enabling far more specific functional and molecular analyses than were previously possible with static images. Finally, Aim 3 introduces an epi-mode deep-UV microscope designed to overcome geometric limitations of transmission-mode systems, enabling label-free imaging of thick, unstained tissues and expanding the technique’s potential for stain- and slide-free histological diagnostics. Together, these studies demonstrate deep-UV microscopy as a simple, accessible, and high-resolution imaging tool for both clinical and research settings.