Antibacterial PLA/PEG electrospun fibers: Comparative study between grafting and blending PEG

Abstract

Antibacterial micro- and nanofibrous materials based on polylactide (PLA) and polyethylene glycol (PEG) were prepared by electrospinning. PEG incorporation was achieved by its physical blending with or chemical grafting on PLA. The role of the incorporation method on the surface wettability, the thermal, the mechanical and the biological properties was studied in relation to mats applicability. Physical blending or chemical grafting did not significantly modify the wettability of the mats, but showed a plasticizing effect on PLA – more obvious in the case of the physical blend fibers in agreement with the higher PEG mobility. The mechanical properties of the mats were also influenced by the PEG incorporation method. Fibrous mats of physically blended PLA and PEG proved quasi-ductile, while brittle behavior was registered for the chemically grafted poly(l-lactide)-graft-polyethylene glycol methyl ether acrylate mats. 5-nitro-8-hydroxyquinoline (5N8Q) was loaded as a model antibacterial drug. The polyether incorporation method proved influencing the 5N8Q release profile with burst effect recorded for all PEG-containing mats. Additionally, all drug-loaded mats presented antibacterial activity against Staphylococcus aureus and Escherichia coli. Thus, the choice of polyether incorporation method is dependent on the targeted application of the antibacterial materials.