Controlling Reactive Species Delivery in Cold Plasma Jets: A key challenge in Plasma Medicine

Objective

Cold atmospheric plasma (CAP) jets are at the forefront of next-generation biomedical technologies in a time of increasing antimicrobial resistance (AMR) and need for non-invasive medical treatments. Their ability to generate reactive oxygen and nitrogen based chemical species at room temperature makes them powerful tools for a wide range of applications, especially in the biomedical field. However, achieving precise control over the delivery of these reactive species in intricate biological environments remains a formidable challenge. The proposed research aims to advance control of CAP jets for precise delivery of reactive species to biological samples. By systematically varying discharge parameters, gas flow, and nozzle geometries, this study seeks to map distinct bifurcation or stable regimes, unraveling the underlying physical mechanisms that govern species delivery. Particular attention will be given to how these regimes modulate flux, spatial distribution, and chemical composition of reactive species, which are critical for biomedical applications addressing biofilm-associated infections and AMR. The interplay between flow-induced discharge topologies will be examined to determine their role in shaping species transport in the plasma jet. Advanced imaging techniques, along with quantitative diagnostics such as Laser-Induced Fluorescence (LIF) and Two-Photon Absorption Laser-Induced Fluorescence (TALIF), will be employed to map these species. To validate the accuracy and localization of reactive species delivery, advanced chemical probes will be employed to trace their transport pathways through biofilm surrogates and real-world biofilms. This approach lays the foundation for translational biomedical applications, with a focus on site-specific treatments targeting biofilm-associated infections. This proposal bridges plasma physics, fluid dynamics, and microbiology, advancing the knowledge needed to translate CAP into a clinically viable tool.