Allylthiourea-mediated self-healing hydrogels based on poly(vinyl alcohol): Enhanced cell viability/biocompatibility and sustained drug release

Abstract

Hydrogel-based materials represent promising candidates for drug delivery. In our research, we synthesized a series of hydrogels—PVATU-1 (2:1), PVATU-2 (1:1), and PVATU-3 (0.5:1)—by adjusting the poly(vinyl alcohol) (PVA) ratio while maintaining a constant ratio of allylthiourea (ATU) monomer and glutaraldehyde cross-linker, aiming to understand their impacts on gelation. These PVATU hydrogels displayed impressive swelling in neutral conditions and exhibited visible self-healing capabilities. Notably, PVATU-1 shows superior mechanical strength among the variants. Surface analysis using AFM and SEM unveiled porous structures within the hydrogels, while thermal stability tests indicated their resilience up to 200°C. DSC analysis revealed minimal variation in glass transition temperatures (Tg), affirming stability. A distinct endothermic peak around 250–350°C across all hydrogels confirmed their semi-crystalline nature, corroborated by powder XRD. Noteworthy, PVATU-1 demonstrated optimal loading and releasing efficiency for levofloxacin, with 74.5% loading and 82.8% releasing efficiency within 18 h. Biocompatibility assessments on HeLa cells affirmed the nontoxicity of PVATU hydrogel treatments. © 2024 Wiley Periodicals LLC.