Multiresponsive Glutathione-Functionalized Waterborne Polyurethane/PEDOT System for Electrically and Redox-Controlled Delivery of an Anticancer Peptide

Prostate cancer remains one of the leading causes of cancer-related mortality. Although there were advances in cancer therapy, there is a need for advanced drug delivery strategies to improve the spatiotemporal control of therapeutic action. Here, we developed conductive, redox-responsive hybrid sponges based on glutathione-extended waterborne polyurethane (WPU-GSSG) and the electroactive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) for dual-stimuli-triggered release of anticancer peptide in locoregional tumor therapy. WPU/PEDOT porous scaffolds presented lightweight and mechanically resilient structures with homogeneous loading of the pentapeptide Cys-Arg-N-methyl-Glu-Lys-Ala (CR(NMe)EKA). PEDOT incorporation significantly enhanced the electrochemical properties of the sponges, providing reversible redox activity, reduced impedance, and near-ideal capacitive behavior. The sponges supported cell adhesion and high cell viability within the three-dimensional architecture. In vitro release studies demonstrated that peptide delivery is regulated by a synergistic combination of redox and electrical stimuli. A mimetic tumor microenvironment accelerated peptide release relative to physiological conditions. Electrostimulation (+0.5 V chronoamperometry) further enhanced release kinetics, and the combined application of redox and electrical triggers enabled peptide release of up to ∼94%, demonstrating tunable stimulus-responsive delivery. Functional assays on cancer cells supported the therapeutic potential of this platform. While WPU alone was fully cytocompatible and PEDOT-containing sponges exhibited moderate electrostimulation-dependent effects, CR(NMe)EKA-loaded conductive sponges induced a pronounced reduction in cancer cell viability under electrostimulation, decreasing survival to ∼20%. Although further in vivo validation is required, these findings highlight the potential of multifunctional WPU/PEDOT sponges for localized, stimuli-responsive peptide delivery.