Biopolymer-enhanced PVA hydrogels for DNA delivery: Structural and functional characterization

Hydrogels are versatile materials with significant potential in biomedical applications, particularly for controlled release systems. In this study, poly(vinyl alcohol) (PVA)-based hydrogels were developed by incorporating chitosan (CHI), poly(ethylene glycol) (PEG), and poly(lactic acid) (PLA) to tailor their physicochemical and mechanical properties. FTIR analysis confirmed successful polymer integration, which influenced the hydrogels’ swelling behavior, viscosity, and thermal stability. Texture profile analysis demonstrated that polymer addition modulated mechanical characteristics such as compressibility, hardness, and cohesiveness, with PVA-CHI showing enhanced structural cohesion. Rheological measurements, including stress and frequency sweep tests, revealed viscoelastic behavior typical of soft hydrogels. The storage modulus (G′) was generally higher than the loss modulus (G″), indicating elastic dominance. PVA-PLA exhibited the highest stiffness, while PVA-CHI maintained structural integrity under deformation. The complex viscosity increased at low frequencies, especially for PVA-PLA, indicating a more robust network. To evaluate the hydrogels’ potential for gene delivery, DNA release studies were performed in PBS. The release was generally low across formulations, with PVA-CHI exhibiting the highest cumulative release. Release kinetics followed a pseudo-second-order model, suggesting a mechanism influenced by both diffusion and interactions between DNA and the polymer matrix. Scanning electron microscopy confirmed structural changes due to polymer blending, affecting both surface and internal morphology. These results demonstrate that the incorporation of specific polymers into PVA hydrogels can be strategically used to modulate their mechanical behavior and drug delivery performance, offering promising potential for biomedical applications such as tissue engineering and gene therapy.