Gold-promoting-satellite to boost photothermal conversion efficiency of Cu2-xSe for triple-negative breast cancer targeting therapy

Copper chalcogenide nanocrystal is a promising photothermal transduction material for photoacoustic imaging and photothermal therapy. But how to ameliorate its photothermal conversion efficiency in a controllable manner is still not well understood. Here, a novel gold-promoting-satellite Cu2-xSe (GPS–CS) nanoparticle was developed by simple in situ reduction. Our simulated models indicated that maintaining the number of gold satellites at ∼10 satellites per Cu2-xSe can significantly boost photothermal conversion efficiency. The GPS-CS exhibited higher photothermal conversion efficiency and less toxicity than the bare Cu2-xSe, and the programmed death-1 (PD-1) modified GPS-CS (GPS–CS@PD-1) nanocomplex presented excellent targeting ability both in vitro and in vivo. We further treated this nanocomplex in TNBC-bearing mice with photothermal targeting therapy (PTTT). The tumor was significantly inhibited or totally ablated; meanwhile, the normocytic normochromic anemia and hepatic metastasis were ameliorated. This work provides an appealing modification strategy for boosting the photothermal conversion efficiency of Cu2-xSe for effective PTTT.