Synergistic Piezoelectricity and Lubrication in an Injectable Hydrogel for Osteochondral Regeneration

ABSTRACT The repair of osteochondral defects remains a challenge due to the limited self‐repair capability of cartilage tissue. We present an injectable, biodegradable hydrogel scaffold integrating piezoelectricity with surface lubrication to mimic the native joint microenvironment. The scaffold comprises a methacrylated gelatin (GelMA) matrix reinforced with piezoelectric poly(L‐lactic acid) (PLLA) fibers, fabricated via in situ photocuring. A poly (2‐methacryloyloxyethyl phosphorylcholine) (PMPC) lubricating layer is subsequently grafted using residual photoinitiators, creating a stable dual‐functional system (G‐P‐M). Mechanistically, the PMPC coating dissipates harmful shear stress, while the internal piezoelectric network converts physiological mechanical loads into electrical signals. This synergistic biophysical modulation significantly enhances the osteogenic and chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and attenuates chondrocyte senescence in vitro. In a rat full‐thickness osteochondral defect model, the G‐P‐M scaffold demonstrated superior regeneration efficacy driven by the combined effects of lubrication and piezoelectric stimulation. This study offers a bioinspired strategy integrating stress dissipation and electrophysiological cues for osteochondral tissue engineering.