Photostability enhancement of silica-coated gold nanostars for photoacoustic imaging guided photothermal therapy

Yingna Chen; Chang Xu; Yu Cheng; Qian Cheng

doi:10.1016/j.pacs.2021.100284

Photostability enhancement of silica-coated gold nanostars for photoacoustic imaging guided photothermal therapy

Photoacoustics. 2021 Jul 17:23:100284. doi: 10.1016/j.pacs.2021.100284. eCollection 2021 Sep.

Authors

Yingna Chen¹, Chang Xu², Yu Cheng², Qian Cheng^{1

3}

Affiliations

¹ Institute of Acoustics, School of Physics Science and Engineering, Tongji University, Shanghai, PR China.
² The Institute for Translational Nanomedicine, Shanghai East Hospital, The Institute for Biomedical Engineering & Nano Science, Tongji University School of Medicine, Shanghai, PR China.
³ The Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopaedics, Tongji Hospital, Tongji University School of Medicine, Shanghai, PR China.

Abstract

Gold nanostars (GNSs) are promising contrast agents for simultaneous photothermal therapy and photoacoustic imaging (PAI) owing to their excellent photothermal conversion efficiency. However, GNSs are easily reshaped under transient high-intensity laser pulses, which can cause a rapid shift in the light absorption peak, resulting in a decrease in both therapeutic and monitoring effects. In this work, we synthesized GNSs without toxic surfactants and coated them with a silica shell to retain their shape, thus maintaining their photostability. The excellent performance of these silica-coated GNSs was verified through both in vitro and in vivo PAI experiments. The silica-coated GNSs exhibited a threefold improvement in photoacoustic stability, as compared with the non-coated GNSs. The proposed silica coating method for GNSs was found to improve the photostability of GNSs, making them efficient, safe, and reliable nanoparticles for PAI.

Keywords: Contrast agent; GNPs, gold nanoparticles; GNSs, gold nanostars; Gold nanostars; MSCs, mesenchymal stromal cells; OPO, optical parametric oscillator; PA, photoacoustic; PAI, photoacoustic imaging; PT, photothermal; PTT, photothermal therapeutic; Photoacoustic imaging; Photoacoustic quantitative evaluation; Photostability.