Integrating Modified Fe₃O₄ Nanoparticles and Nisin with T4 Bacteriophage for Enhanced Biofilm Eradication

Biofilm formation presents significant challenges in healthcare, food processing, and water treatment, contributing to antibiotic resistance and persistent infections. Effective strategies to combat biofilm-associated infections are urgently needed. This study introduces a novel approach to biofilm removal by bio-functionalizing T4 bacteriophage with modified Fe₃O₄ nanoparticles (NPs) and Nisin, an antibacterial peptide, to form the Fe₃O₄-Phage-T4 + Nisin complex. The aim is to enhance antimicrobial efficacy and biofilm eradication. The Fe₃O₄-Phage-T4 + Nisin complex was synthesized by conjugating T4 bacteriophage with modified Fe₃O₄ NPs and Nisin. The antimicrobial and antibiofilm activity of the complex was evaluated against multidrug-resistant Pseudomonas aeruginosa strains (PA01 and PA14) using biofilm inhibition and eradication assays. Stability and efficacy were further tested across a pH range of 5 to 8. The Fe₃O₄-Phage-T4 + Nisin complex exhibited superior biofilm removal compared to its individual components. The integration of Nisin broadened the antibacterial spectrum, targeting both Gram-positive and Gram-negative bacteria, while the modified Fe₃O₄ NPs enhanced phage penetration and bacterial cell disruption. The complex demonstrated significant biofilm inhibition and eradication, addressing the challenge of biofilm-related antibiotic tolerance, which often necessitates high antibiotic doses. Additionally, it maintained stability and efficacy across varying pH conditions.