Molecular engineering of organic-based agents for bioimaging and phototherapeutics.

monitoring of the location and transportation of bioactive molecules is essential for deciphering diverse biological events in the field of biomedicine. In addition, obtaining the information of lesions will provide a clear perspective for surgeons to perform precise resection in clinical surgery. Notably, delivering drugs or operating photodynamic therapy/photothermal therapy by labeling the lesion regions of interest can improve treatment and reduce side effects . In various advanced imaging and therapy modalities, optical theranostic agents based on organic small molecules can be conveniently modified as needed and can be easily internalized into cells/lesions in a non-invasive manner, which are prerequisites for bioimaging and precision treatment. In this tutorial review, we first summarize the molecular immobilization strategies to retain small-molecule agents inside cells/lesions to prevent their diffusion in living organisms. Emphasis will be focused on introducing the application of these strategies for imaging of biomolecules and precision treatment, particularly pertaining to why targeting therapy is required.