An Injectable Metal-Phenolic Network Hydrogel for Coordinated PRP Delivery in Osteoarthritis Treatment

Osteoarthritis (OA) is a highly prevalent degenerative joint disease affecting over 500 million people globally, imposing substantial social and economic burdens. Current treatments, including platelet-rich plasma (PRP), are limited by rapid growth factor release, failing to achieve long-term efficacy. To address this, we developed an injectable PRP-loaded hydrogel via in situ assembly of metal-phenolic networks (MPNs), leveraging MPNs' multi-scale porous structure, adjustable mesh size, and dynamic drug interactions to enable "dynamic adhesion" and sustained growth factor release.In vitro studies with OA chondrocytes demonstrated stable PRP release for 14 days, while in vivo evaluations in OA rodent (rat) models confirmed therapeutic effects, including anti-inflammatory, antioxidant, and cartilage repair-promoting activities.This MPN-based hydrogel system validates a novel strategy for sustained PRP delivery, offering a convenient, safe, and effective approach to enhance long-term OA treatment outcomes with potential for clinical translation.