Engineering the CeO2 Layer on Gold Nanopyramids for Enhanced Near- infrared Photothermal Conversion

Abstract

Gold-based core-shell oxides show great potential in photothermal theranostics, but their applications are limited by the inability for precise regulation of light absorption property. Here, we develop a kind of gold bipyramid covered by a cerium oxide layer (ACH) with tunable thickness to enhance the near-infrared light absorption and photothermal conversion efficiency. The anisotropic feature enables ACH with a strong light absorption at a wavelength of 1064 nm, accompanied by as high as 56.2 % photothermal efficiency. Both in vitro and in vivo results demonstrate that ACH possesses the capabilities for dual-modality molecular targeted imaging and efficient tumor inhibition via photothermal therapy. Moreover, the integration of CT and photoacoustic imaging capabilities of ACH nanoparticles show real-time feedback during synergy treatment, enabling timely monitoring and adjustment of therapeutic procedures. This work reveals the impact of metal oxide layer on the photothermal performance of plasmonic nanostructures, providing a new strategy for near-infrared theranostics.