Advancing biomedical applications via manipulating intersystem crossing

Precision diagnosis and treatment have received increasing attention for modern medicine, and the optical imaging and therapeutic techniques (e.g., fluorescence imaging, photoacoustic imaging, time-resolved imaging, photodynamic therapy, and photothermal therapy) have greatly advanced this field. It is now becoming very clear that the photophysical properties play a central role in determining the biomedical function and efficiency of optical agents, thus it is extremely important to make as much absorbed energy as possible to dissipate in the desired pathway for maximized biomedical applications. During energy transition processes, intersystem crossing (ISC) is a crucial step that determines many fundamental photochemical and photophysical phenomena, such as photodynamic therapy, room-temperature phosphorescence, and thermally activated delayed fluorescence. Therefore, the manipulation of ISC process of organic molecules will greatly advance the development of high-performance phototheranostic agents. Thus far, although a few of review papers have summarized some achievements in optical imaging or therapeutic materials, few of them have concentrated on how to boost the photophysical properties and biomedical applications by tuning the ISC-related energy transfer process of organic molecules. In this review, we highlight the recent progresses of organic molecular probes for biomedical applications that are achieved via rational molecular design especially by manipulating the ISC-related photophysical process. The perspectives and challenges for future phototheranostic agent development via regulating ISC process are also discussed. This review aims to provide guidance for the design of organic optical agents with optimal energy transformation to maximize their performance in desired biomedical applications and in precision medicine.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

Precision diagnosis and treatment in modern medicine require advanced optical imaging and therapeutic techniques. The manipulation of inter system crossing (ISC) process of organic molecules can greatly advance the development of high-performance phototheranostic agents.