Synergistic Integration of α-Ag2WO4 into PLA/PBAT for the Development of Electrospun Membranes: Advancing Structural Integrity and Antimicrobial Efficacy.

Abstract

The rising resistance of various pathogens and the demand for materials that prevent infections drive the need to develop broad-spectrum antimicrobial membranes capable of combating a range of microorganisms, thereby enhancing safety in biomedical and industrial applications. Herein, we introduce a simple and efficient technique to engineer membranes composed of polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT) biopolymers and α-Ag2WO4 particles using an electrospinning technique. The corresponding structural, thermal, mechanical, and antimicrobial properties were characterized. X-ray diffraction (XRD) patterns confirmed the integration of crystalline α-Ag2WO4 within the polymer matrix. Scanning electron microscopy (SEM) and Raman confocal microscopy revealed uniformly dispersed α-Ag2WO4 particles in the electrospun fibers, influencing their diameter and surface roughness. Thermal analysis indicated adjustments in the thermal stability and crystallinity of the composites with an increasing α-Ag2WO4 content. Dynamic mechanical analysis (DMA) highlighted variations in storage modulus and glass transition temperatures due to interactions between α-Ag2WO4 and polymer chains, with tensile tests showing an increase in elastic modulus and ultimate tensile strength as the α-Ag2WO4 content increased. Antimicrobial assessments revealed that PLA/PBAT membranes with α-Ag2WO4 showed pronounced antibacterial activity, forming inhibition halos across all samples against Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and Mycobacterium smegmatis (a surrogate for Mycobacterium tuberculosis). These membranes also exhibited potent antiviral activity against bacteriophage phi 6, a surrogate for SARS-CoV-2, suggesting potential applications in combating infections caused by enveloped viruses. The antimicrobial activities are attributed to the generation of reactive oxygen species (ROS) and the controlled release of Ag+ ions. This work underscores the multifaceted capabilities of α-Ag2WO4-enhanced PLA/PBAT membranes in combating bacterial and viral growth, where both durability and microbial resistance are critical. Taken together, our findings provide a solution for obtaining advanced materials to be applied in a wide range of industrial applications, such as filtration systems, food preservation, antimicrobial coatings, protective textiles, and cleaning products.