Doctoral Student, Victor Choi, successfully defends Viva

Victor’s dissertation titled, “Development of New Ultrasound Sensitive Antimicrobial Therapeutics for Antibiofilm Therapy” contributes towards addressing the global challenge of antimicrobial resistance (AMR) by combining targeted drug delivery and mechanical disruption of biofilm structures.

Antimicrobial resistance is a global concern, as chronic and hospital-acquired infections are already becoming harder to treat because of the rise in antibiotic-resistant bacteria. In most of these infections, bacteria form protective layers called biofilms, which make them much harder to kill with regular antibiotics or the body’s immune system.

Even though new treatments have been tried, they often fail to fully break down these biofilms or kill the bacteria hiding inside, especially the ones that are inactive but can later cause the infection to come back. When infections return, the bacteria are often even more resistant to drugs.

To help solve this problem, Vicor developed a new treatment approach, as part of his doctoral research, using ultrasound-sensitive particles called AURAs (tiny droplets loaded with antibiotics). When hit with ultrasound, these droplets burst and physically break apart the biofilm, allowing the antibiotics to reach and kill the bacteria more effectively.

Lab tests showed that this method:

• Delivered antibiotics into bacteria 5.5 times better,
• Made the treatment 44 times more effective,
• Broke up the biofilm and killed even the dormant bacteria.

Further tests in laboratory-and animal models also showed that this method worked well at lower drug doses and cleared infections more effectively than antibiotics alone. This novel research illustrates that using ultrasound to help deliver antibiotics could be a powerful new way to treat stubborn infections and fight antibiotic resistance.

Victor reflected on the process, “A PhD is a slow and often solitary process of transformation, beginning with a single question and unfolding into years of late nights questioning a hypothesis. Marked by frustrating setbacks, (un)patient untangling of unfamiliar concepts, and those rare moments of breakthrough, I thank my supervisors, Prof Eleanor Stride and Prof Dario Carugo, for helping me navigate this intellectual and personal challenge. I also extend my sincerest gratitude to my examiners, Prof Man-Wah Tan and Prof Matthew Costa, for dedicating their expertise. Your exacting standards and probing questions were precisely what I needed, providing a conversation that was as challenging as it was insightful.”

*Funded by the Engineering and Physical Sciences Research Council (EPSRC) under Programme Grant Scheme EP/V026623/1.