Antibacterial nanofibers based on poly(L-lactide-co-D, L-lactide) and poly(vinyl alcohol) used in wound dressings potentially: a comparison between hybrid and blend properties

Morphology, hydrophilicity, degradation, mechanical properties, drug release, bacterial resistance, and cell viability are indispensable parameters for a bioactive wound dressing. In this work, the aforementioned terms between hybrid and blend nanofibrous samples based on poly (L-lactide-co-D, L-lactide) (PLDLLA) and poly (vinyl alcohol) (PVA) containing triclosan (Tri) as an antibacterial drug were investigated. The FE-SEM images showed that the presence of Tri in the hybrid and blend samples led to bimodal, and unimodal diameter size distributions. The FTIR spectra revealed that the addition of PVA caused to shift the carbonyl bond of PLDLLA in the blend sample, and DSC thermograms exhibited the immiscibility of PVA and PLDLLA polymers in the blend. Moreover, the hybrid sample showed higher hydrophilicity with water contact angle (WCA) of 53 than the blend ones with WCA of 73 which proved by water up-take test. In the following, the antibacterial evaluation showed better results for hybrid-Tri with the maximum growth inhibitory zones of 35 mm and 48 mm for E. coli and S. aureus, respectively. On the other hand, the hybrid nanofibrous sample showed remarkable mechanical properties (tensile stress similar to 19 MPa, and Young's modulus similar to 532 MPa). Finally, the SNL 76/7 fibroblast cell line culture confirmed that the hybrid-Tri nanofibrous sample had better proliferation performance than the blend-Tri sample because of the minimal cytotoxicity and maximal cell viability by MTT and acridine orange/ethidium bromide staining.