Early diagnosis and treatment of osteoarthritis with a Au@PDA-WL NP nano-probe by photoacoustic imaging.

A photoacoustic imaging (Au@PDA-WL NPs) probe was successfully prepared for monitoring the early degeneration of articular cartilage. WYRGRL immobilized on the surface of Au@PDA NPs could target the collagen II peptide, which is expressed on chondrocytes and , and the enrichment of this nano-probe on cartilage tissue further resulted in the localized plasmon resonance coupling effect, inducing an enhancement in photothermal conversion capacity after the formation of aggregates. Besides, the catechol structure in the PDA shell could eliminate ROS to effectively delay the development of osteoarthrosis.