Nickel Nanoparticles/Recycled Polyethylene Terephthalate Nanofibers Reduce AlgD Expression in Pseudomonas aeruginosa

Background and objectives: Recycled polyethylene terephthalate (RPET) nanofibers have become an important part of human life, with a continuous increase in their production and consumption. Herein, the antibacterial activity of nickel nanoparticles/recycled polyethylene terephthalate nanofibers (NiNP/RPET NF web) was evaluated by analyzing alginate expression in Pseudomonas aeruginosa, as an opportunistic microorganism. Methods: NiNPs were synthesized and NiNP/RPET NF was produced by adding 25 μg/ml of NiNP to 10% solutions of RPET at a weight ratio of 3%. After exposing P. aeruginosa (PA01) to NiNP/RPET NF, the biofilm-forming capacity was determined and real-time PCR was performed to measure algD expression. Results: Treatment with 25 μg/ml of NiNP/RPET NF reduced growth of P. aeruginosa on Mueller Hinton agar but did not result in complete inhibition. The biofilm optical density (550 nm) was 0.464 ± 0.021 after treatment with NiNP/RPET NF and 0.082± 0.011 in the absence of NiNP/RPET NF. This indicates the significant reduction of biofilm formation after exposure to NiNP/RPET NF (p=0.01). In addition, a 0.6-fold (p=0.03) reduction in alginate expression was detected by real-time quantitative real-time PCR. Conclusion: Our results indicate the potential of NiNP/RPET NF for application in nano-based antibacterial medical systems.