D-A-D structured selenadiazolesbenzothiadiazole-based near-infrared dye for enhanced photoacoustic imaging and photothermal cancer therapy

Near-infrared (NIR) small molecular organic dyes as photothermal agents for cancer photothermal therapy (PTT) have attracted considerable research attention. Herein, two donor-acceptor-donor (D-A-D) structured NIR dyes, BBTT and SeBTT, are rationally designed, where the only difference is one heteroatom within the acceptor unit varying from sulfur to selenium (Se). More importantly, SeBTT NPs exhibit stronger NIR absorbance and higher photothermal conversion efficiency (PTCE approximate to 65.3%). In vivo experiments illustrate that SeBTT NPs can be utilized as a high contrast photoacoustic imaging (PAI) agent, and succeed in tumor suppression without noticeable damage to main organs under NIR photoirradiation. This study presents an effective molecular heteroatom surgery strategy to regulate the photothermal properties of NIR small molecules for enhanced PAI and PTT. (C) 2021 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

Two donor-acceptor-donor (D-A-D) structured NIR dyes, BBTT and SeBTT, were designed, with SeBTT NPs showing stronger NIR absorbance and higher photothermal conversion efficiency. In vivo experiments demonstrated that SeBTT NPs can be used as a high contrast photoacoustic imaging agent and effectively suppress tumors under NIR photoirradiation.