A Highly Efficient Red Metal-free Organic Phosphor for Time-Resolved Luminescence Imaging and Photodynamic Therapy

• Published in: ACS applied materials & interfaces Vol. 11; no. 20; pp. 18103 - 18110
• Main Authors: Shi, Huifang, Zou, Liang, Huang, Kaiwei, Wang, He, Sun, Chen, Wang, Shan, Ma, Huili, He, Yarong, Wang, Jianpu, Yu, Haidong, Yao, Wei, An, Zhongfu, Zhao, Qiang, Huang, Wei
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 22.05.2019
• Subjects: organic phosphorescence; organic semiconductor; time-resolved luminescence imaging; crystal engineering; photodynamic therapy
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.9b01615

Developing highly efficient red metal-free organic phosphors for biological applications is a formidable challenge. Here, we report a novel molecular design principle to obtain red metal-free organic phosphors with long emission lifetime (504.6 μs) and high phosphorescence efficiency (14.6%) from the isolated molecules in the crystal. Furthermore, the well-dispersed phosphorescent nanodots (PNDs) with the particle size around 5 nm are prepared through polymer-encapsulation in an aqueous solution, which show good biocompatibility and low cytotoxicity. The metal-free PNDs are successfully applied to time-resolved luminescence imaging to eliminate background fluorescence interference both in vitro and vivo as well as effective photodynamic anticancer therapy for the first time. This work will not only pave a pathway to develop highly efficient metal-free RTP materials but also expand the scope of their applications to biomedical fields.