Electrospun Polylactic Acid-Based Fibers Loaded with Multifunctional Antibacterial Biobased Polymers

Abstract

Here, we report the development of antibacterial and compostable electrospun polylactic acid (PLA) fibers by incorporation of a multifunctional biobased polymer in the process. The multifunctional polymer was synthesized from the bio-sourced itaconic acid building block by radical polymerization followed by click chemistry reaction with hydantoin groups. The resulting polymer possesses triazole and hydantoin groups available for further N-alkylation and chlorination reaction, which provide antibacterial activity. This polymer was added to the electrospinning PLA solution at 10 wt %, and fiber mats were successfully prepared. The obtained fibers were surface-modified through the accessible functional groups, leading to the corresponding cationic triazolium and N-halamine groups. The fibers with both antibacterial functionalities demonstrated high antibacterial activity against Gram-positive and Gram-negative bacteria. While the fibers with cationic surface groups are only effective against Gram-positive bacteria (Staphylococcus epidermidis and Staphylococcus aureus), upon chlorination, the activity against Gram-negative Escherichia coli and Pseudomonas aeruginosa is significantly improved. In addition, the compostability of the electrospun fibers was tested under industrial composting conditions, showing that the incorporation of the antibacterial polymer does not impede the disintegrability of the material. Overall, this study demonstrates the feasibility of this biobased multifunctional polymer as an antibacterial agent for biodegradable polymeric materials with potential application in medical uses.

Figure 1

Synthesis route of the antibacterial biobased polymer P(DMHICl-Q).

Figure 2

FTIR spectra of the antibacterial biobased polymer P(DMHICl-Q) and its precursors P(PrI), P(Boc-DMHI), and P(DMHI-Q).

Figure 3

SEM micrographs and their corresponding histograms of fiber diameters of (a) PLA and (b) PLA/P(DMHI) fiber mats.

Figure 4

Visual appearance and SEM images of the tested PLA and PLA/P(DMHICl-Q) fiber mats over time under composting conditions.

Figure 5

(a) SEM image of PLA and PLA/P(DMHICl-Q) fibers taken after 42 days of composting incubation. (b) Average fiber diameter of PLA and PLA/P(DMHICl-Q) fiber mats over time under composting conditions.

Figure 6

Disintegration degree of PLA and PLA/P(DMHICl-Q) fiber mats over time under composting conditions.