Enhanced antibacterial nanocomposite mats by coaxial electrospinning of polycaprolactone fibers loaded with Zn-based nanoparticles

• Published in: Nanomedicine Vol. 14; no. 5; pp. 1695 - 1706
• Main Authors: Prado-Prone, Gina, Silva-Bermudez, Phaedra, Almaguer-Flores, Argelia, García-Macedo, Jorge A., García, Victor I., Rodil, Sandra E., Ibarra, Clemente, Velasquillo, Cristina
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2018
• Subjects: Anti-Bacterial Agents - administration & dosage; Anti-Bacterial Agents - chemistry; Antibacterial nanocomposites; Bandages; Coaxial electrospinning; Escherichia coli - drug effects; Escherichia coli - growth & development; Nanofibers - administration & dosage; Nanofibers - chemistry; Nanotechnology; Polycaprolactone; Polyesters - chemistry; Staphylococcus aureus - drug effects; Staphylococcus aureus - growth & development; Zinc Acetate - administration & dosage; Zinc Acetate - chemistry; Zinc Oxide - administration & dosage; Zinc Oxide - chemistry; Zn acetate; ZnO nanoparticles; Antibacterial nanocomposites; ZnO nanoparticles; Zn acetate; Polycaprolactone; Coaxial electrospinning
• ISSN: 1549-9634; 1549-9642
• DOI: 10.1016/j.nano.2018.04.005

ZnO and Zn acetate nanoparticles were embedded in polycaprolactone coaxial-fibers and uniaxial-fibers matrices to develop potential antibacterial nanocomposite wound dressings (mats). Morphology, composition, wettability, crystallinity and fiber structure of mats were characterized. Antibacterial properties of mats were tested against E. coli and S. aureus by turbidity and MTT assays. The effect of UVA illumination (prior to bacteria inoculation) on mats’ antibacterial activity was also studied. Results showed that a coaxial-fibers design maintained nanoparticles distributed in the outer-shell of fibers and, in general, enhanced the antibacterial effect of the mats, in comparison to conventional uniaxial-fibers mats. Results indicated that mats simultaneously inhibited planktonic and biofilm bacterial growth by, probably, two main antibacterial mechanisms; 1) release of Zn2+ ions (mainly from Zn acetate nanoparticles) and 2) photocatalytic oxidative processes exerted by ZnO nanoparticles. Antibacterial properties of mats were significantly improved by coaxial-fibers design and exposure to UVA-light prior to bacteria inoculation. Zn-based (ZnO and Zn acetate) nanoparticles were embedded in coaxial-fibers and uniaxial-fibers polycaprolactone matrices to develop potential antibacterial wound dressings. Coaxial-fibers mats (nps in the outer-shell of fibers) proved to be more efficient by showing similar (or improved) antibacterial effects than those of their corresponding uniaxial-fibers mats, but having smaller amounts of nanoparticles than their counterparts. Antibacterial tests against E. coli and S. aureus indicated that mats, probably, exerted two main antibacterial mechanisms, releasing of Zn2+ ions and photocatalytic ROS generation, which together allowed inhibition of planktonic and biofilm bacterial growth and improvement of mats antibacterial properties upon UVA-light exposure. [Display omitted]