The present paper is focused on the surface and bulk characterization of poly(lactic acid) (PLA)-based composites that contain hydrolyzed collagen as a biological polymer, silver nanoparticles and vitamin E and epoxidized soybean oil as a plasticizer. The bionanocomposites were obtained by melt processing and evaluated for structural and surface characteristics, biocompatibility, functional properties such as antimicrobial and antioxidant activity and hydrolytic degradation behavior. It has been established that the optimal composition to impart functional properties to the PLA matrix is a formulation containing 15% epoxidized soybean oil, 15% hydrolyzed collagen, 5% Pluronic, 5% vitamin E and 0·3% silver nanoparticles. This bionanocomposite inhibits the growth of both Gram-positive bacteria, Escherichia coli and Salmonella typhimurium, and Gram-negative bacteria, Listeria monocytogenes, and reaches 100% radical-scavenging activity. The PLA-based biomaterials obtained in this study are stable in biological media in the short and medium terms and therefore are recommended as multifunctional biomaterials for the manufacture of medical devices, such as urinary catheters.