Electroconductive Agarose–Gelatin Hydrogels for Tissue Engineering: Formulation, Characterization, Protein Release and Biocompatibility

ABSTRACT In this study, electroconductive hydrogels were developed by combining agarose and gelatin (AgaGel) with in situ polymerized polyaniline (PAni) and polypyrrole (PPy) with the aim of obtaining multifunctional scaffolds for tissue engineering applications. The base AgaGel formulation was optimized by varying agarose and gelatin concentrations and evaluating their rheological behavior and swelling properties, identifying a composition that provided a suitable balance between stiffness and structural stability. Conductive domains were subsequently introduced through oxidative polymerization of PAni and PPy within the hydrogel network. Both conductive polymers significantly increased electrical conductivity while preserving the viscoelastic properties of the matrix. Structural analyses confirmed the successful integration of conductive phases and modifications of the internal porous architecture. Protein release experiments using bovine serum albumin (BSA) revealed controlled release behavior across all formulations. The base AgaGel and PAni‐containing hydrogels followed Fickian diffusion kinetics, whereas the PPy‐modified hydrogel exhibited anomalous transport behavior, likely due to stronger polymer–protein interactions that reduced the total released amount. Cytocompatibility studies further revealed distinct biological responses depending on the conductive polymer: while AgaGel and PPy‐containing systems maintained cell viability comparable to controls, PAni‐modified hydrogels induced a significant reduction in viability.