Single-walled carbon nanohorns-based smart nanotheranostic: From phototherapy to enzyme-activated fluorescence imaging-guided photodynamic therapy

Phototheranostics, a local non-invasive approach that integrates light-based diagnostics and therapeu-tics, enables precise treatment using nanotheranostic agents with minimal damage to normal tissues. However, ensuring high-efficiency ablation of cancer cells using phototheranostics for one time irradia-tion is highly challenging. Herein, we designed and synthesized a single-walled carbon nanohorns-based nanotheranostic agent, HA-IR808-SWNHs, by loading IR808, a photosensitizer, conjugated hyaluronic acid (HA) with an amide bond on the surface of single-walled carbon nanohorns (SWNHs) through non -covalent p -p interaction by the sonication method. The HA in HA-IR808-SWNHs improves the water dis-persibility of SWNHs and endows SWNHs with targeting capabilities. Importantly, overexpressed endogenous hyaluronidase in cancer cells actively disassembles HA-IR808-SWNHs, forming small HA-IR808 fragments. The fragments exhibit a strong fluorescence signal and can be used to guide pro-grammed photodynamic therapy for sequentially eliminating the residual living cancer cells. The current study confirms that HA-IR808-SWNHs is an endogenous enzyme-responsive nanotheranostic agent that can be employed to precisely track and ablate residual cancer cells in a spatiotemporal manner. The results strengthen the understanding of SWNH functionalization and expand its potential biomedical application, especially in cancer theranostics. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

Phototheranostics is a precise treatment method that integrates light-based diagnostics and therapeutics, minimizing damage to normal tissues. In this study, a nanotheranostic agent, HA-IR808-SWNHs, was designed and synthesized, which can be employed to precisely track and ablate cancer cells in a spatiotemporal manner using an endogenous enzyme.