Graduate Defense: Michael Okebiorun

Dissertation Information

Title: Selective Bacterial Biofilm Removal Using Image-Guided Detection And Cold Atmospheric Pressure Plasma

Program: Doctor of Philosophy in Biomedical Engineering

Advisor: Dr. Jim Browning, Electrical and Computer Engineering

Committee Members: Dr. Kenneth A Cornell, Chemistry and Biochemistry (Co-Chair); Dr. Elisa H BarneySmith, Electrical and Computer Engineering; Dr. Nirmala Kandadai,  Electrical Engineering; and Dr. Don Plumlee, Mechanical and Biomedical Engineering

Abstract

This dissertation explores the use of cold atmospheric pressure plasma (CAP) technology in eradicating bacterial biofilms from tissue surfaces, using Ps. fluorescens on chicken tissue to model human chronic wounds. It introduces a novel image-guided technique for precise biofilm removal, employing trypan blue staining coupled with advanced computer vision analysis, enhancing the CAP treatment’s precision and efficacy. The study demonstrates the CAP device’s ability to effectively disrupt biofilms through a non-thermal mechanism, based on its electrical characteristics and operational parameters. The success of the treatment is evident in the significant reduction of biofilm thickness of 49 -185 µm. Post-treatment analyses of treatment configurations, including fluorescent imaging and CFU analysis, reveal a 93-99% reduction in biofilms. Additionally, 3D microscopic imaging shows effective biofilm removal with an etch rate of 2.2–5.8µm/s, further validating the treatment’s success. In summary, this research highlights the potential of CAP technology in addressing bacterial biofilm infections, marking a significant advancement in healthcare, particularly in wound care and infection control.