A self-degradable nanostructured phthalocyanine assembly with high photothermal efficacy to enhanced biosecurity in photothermal therapy

Photothermal therapy (PTT) possesses a great promise for tumor therapy due to its effective tumor inhibition and minimal invasiveness. Nevertheless, most of organic photothermal agents (PTAs) suffer from poor photothermal conversion efficiency, and the residues of PTAs may cause the problem of side effects. Herein, we utilize a molecular surgery approach to develop a self-degradable nanostructured PTA (NanoPcDA2). NanoPcDA2 exhibited a remarkable photothermal conversion efficiency. In addition, NanoPcDA2 showed an outstanding tumor accumulation after intravenous injection, and 92% tumor growth was suppressed in the mice tumor model at a low light dose of 300 J cm(-2) and a NanoPcDA2 dose of 0.8 nmol g(-1). Moreover, NanoPcDA2 can be degraded by singlet oxygen (O-1(2)) produced by itself and lose its photoactivity after PTT. Notably, the photodegradation products of NanoPcDA2 have negligible cytotoxicity. In this way, it not only contributes to resolve the potential phototoxicity problems of residual PTAs, but also can expedite the metabolism of PTAs to avert the potential biotoxicity of drug accumulation.

Automated summary

A self-degradable nanostructured photothermal agent with high photothermal conversion efficiency was developed using a molecular surgery approach. This agent showed excellent efficacy in inhibiting tumor growth at a low light dose, and its degradation products had negligible cytotoxicity.