Cross-linked poly(vinyl alcohol)/citric acid electrospun fibers containing imidazolium ionic liquid with enhanced antiadhesive and antimicrobial properties

Abstract

Patients in hospital environments are susceptible to bacterial colonization, which can lead to infections. In this study, electrospun fibers were manufactured using poly(vinyl alcohol) (PVA) crosslinked with citric acid (CA) and incorporating the ionic liquid (IL) 1-hexadecyl-3-methylimidazolium chloride (C16MImCl) to prevent microbial growth and biofilm formation. The presence of CA and IL reduced the surface tension of the PVA solution (12% w/v) from 52.07 mN/m to 35.84 mN/m. CA was introduced into PVA solutions, and the resulting fibers were thermally crosslinked through esterification between PVA hydroxyl groups and CA. X-ray photoelectron spectroscopy (XPS) confirmed the presence of IL on the fiber surfaces. The IL acted as a surfactant, imparting plasticity to the electrospun fibers and enhancing homogeneity and mechanical properties. Before crosslinking, the PVA/CA/IL fibers exhibited an elongation at break (%) of approximately 140%, a tensile strength of 5.3 MPa, and an elastic modulus of 18.2 MPa. After cross-linking, the elongation at break reduced to 86%, the tensile strength increased to 7.6 MPa, and the elastic modulus increased to 88 MPa. Mechanical measurements confirmed the thermal crosslinking of the fibers, primarily because of the increased elastic modulus. Adhesion and proliferation tests with Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) indicated reduced bacterial adhesion and growth on the PVA/CA/IL fibers. Antimicrobial assays further confirmed a 50.73% and 69.42% increase in bactericidal activity against S. aureus and P. aeruginosa, respectively. The PVA/CA/IL fibers exhibit promising potential for producing antimicrobial materials to prevent the attachment and proliferation of microbial strains on solid surfaces.