Antibacterial sterilization performance of fluorosiloxane acrylate enhanced by magnetic field-assisted plasma

Infection risks of orthokeratology lenses remain a serious clinical challenge. In this study, cross-field magnetic field-enhanced plasma was used to modify fluorosilicone acrylate substrates, with the magnetic field parallel to the substrate surface and perpendicular to the electric field. Different from conventional chemical modification, this strategy physically confines charged particles via the Lorentz force. In situ spectral characterization shows that the magnetic field converts electron linear motion into elongated helical trajectories, prolonging electron residence time and increasing atomic oxygen emission intensity by 98% at 20 W without changing chemical reaction pathways. Such physical regulation optimizes the synergistic effect of hydroxyl radicals and oxygen atoms, switching the bactericidal mechanism from surface membrane destruction to deep intracellular oxidation. The modified surface integrates micro-nano topography and superhydrophilicity. The Si-O network produces a physical cage effect to inhibit bacterial spread, while the hydration layer prevents initial bacterial adhesion. At 15 W for 18 min, both E. coli and S. aureus were inactivated to below the detection limit, while the adhesion of S. aureus fell by up to 86.45%. This work achieves precise magnetic modulation of plasma kinetics, overcoming antibacterial efficiency bottlenecks and offering a low-energy, dual-functional antibacterial strategy for biomedical implants.