Photothermal-responsive polydopamine magnetic nanomotors with anti-inflammatory and anti-oxidative properties for thrombolysis

Recombinant tissue plasminogen activator (rt-PA) is the standard thrombolytic agent that clinical guidelines recommend, while its administration is often associated with systemic bleeding risks. Here, we present a novel photothermal-responsive magnetic nanomotor (rPMP) for safe rt-PA thrombolysis. rPMP comprises Fe 3 O 4 cores and mesopore SiO 2 shells for rt-PA loading, facilitating rapid response to magnetic fields and delivery of rt-PA at the thrombus site. In addition, polydopamine (PDA) is coated around the outermost layer of rPMP to alleviate endothelial oxidative stress, suppress pro-inflammatory cytokine expression (TNF‑α by 32.8%, IL‑6 by 30.4%) via the Wnt signaling pathway, and facilitate thrombolysis through the photothermal effect. In a rat femoral artery thrombosis model, the rPMP-treated group exhibited the most potent thrombolytic efficacy, with only 13.2% of the thrombus area remaining post-treatment. Thus, we believe that the photothermal-responsive magnetic nanomotors represent a promising therapeutic platform for clinical thrombolysis.