Electrospun membranes (EMs) have a wide range of applications, including use as local delivery systems. In this study, we manufactured a polyurethane Tecoflex™ EM loaded with bismuth-based lipophilic nanoparticles (Tecoflex™ EMs-BisBAL NPs). The physicochemical and mechanical characteristics, along with the antitumor and bactericidal effects, were evaluated using a breast cancer cell line and methicillin-susceptible and resistant (MRSA). Drug-free Tecoflex™ EMs and Tecoflex™ EMs-BisBAL NPs had similar fiber diameters of 4.65 ± 1.42 µm and 3.95 ± 1.32 µm, respectively. Drug-free Tecoflex™ EMs did not negatively impact a human fibroblast culture, indicating that the vehicle is biocompatible. Tecoflex™ EMs-BisBAL NPs increased 94% more in size than drug-free Tecoflex™ EMs, indicating that the BisBAL NPs enhanced hydration capacity. Tecoflex™ EMs-BisBAL NPs were highly bactericidal against both methicillin-susceptible and MRSA clinical isolates, inhibiting their growth by 93.11% and 61.70%, respectively. Additionally, Tecoflex™ EMs-BisBAL NPs decreased the viability of MCF-7 tumor cells by 86% after 24 h exposure and 70.1% within 15 min. Regarding the mechanism of action of Tecoflex™ EMs-BisBAL NPs, it appears to disrupt the tumor cell membrane. In conclusion, Tecoflex™ EMs-BisBAL NPs constitute an innovative low-cost drug delivery system for human breast cancer and postoperative wound infections.