Inflammatory-Directed Nanomotors for Targeted Osteoarthritis Treatment.

Current therapeutic strategies for osteoarthritis (OA) predominantly rely on pharmacological interventions; however, the limited bioavailability of these drugs poses a significant challenge. Here, a self-propelled Janus nanomotor is presented for inflammatory-directed target therapy of OA. This system comprises platinum-catalyzed cannabidiol-loaded mesoporous silica nanoparticles encapsulated in chitosan (Pt-CBD/MSN@CS). Upon injection, the Pt face decomposes the hydrogen peroxide (H2O2) fuel produced from the inflammatory microenvironment. This enables positive chemotactic movement along the concentration gradient of H2O2 and effective accumulation at the lesion sites. The targeting efficiency of inflammatory chondrocytes is enhanced by 1.5-fold compared to normal chondrocytes. The low pH in the inflammatory microenvironment triggers the release of CBD, which alleviates oxidative stress, inflammation, and neuropathic pain, and reduces cartilage loss, joint swelling, and osteophyte volume without significant side effects. This nanorobotic delivery strategy offers a promising approach for targeted OA treatment.