ABSTRACT Two‐photon excitation (TPE) phototherapy provides high spatial resolution and deep‐tissue penetration with minimal invasiveness. In this study, we introduce a modular and scalable approach to transform a traditional TPE imaging dye into a highly effective type‐I photosensitizer (PS) through minimal chemical modification. The newly developed selenium‐bridged dye demonstrates pronounced two‐photon absorption, efficient ROS generation upon TPE, and strong antitumor activity both in vitro and in hypoxic in vivo tumor environments. For subcellular targeting, we conjugated organelle‐specific functional groups to produce a series of derivatives, thereby achieving accurate ROS localization and improved PDT efficacy. Leveraging the amphiphilic properties of these PSs, we established a self‐assembled dye‐combination micelle (DCM) approach that enables the co‐assembly of membrane‐ and mitochondria‐targeted derivatives into stable, carrier‐free nanoparticles. This multi‐dye strategy facilitates enhanced phototoxicity by simultaneously impairing multiple organelle functions. Additional surface modification using the RGD (Arg‐Gly‐Asp) peptide sequence imparts tumor selectivity through α v β 3 integrin‐mediated uptake, yielding DCM nanoparticles that selectively induce phototoxic effects in cancer cells while sparing healthy tissue. Importantly, this platform demonstrates spatially restricted, two‐photon‐triggered therapeutic efficacy in freshly excised human colon tumor tissue, emphasizing its potential for clinical translation.
Lee et al. (Sat,) studied this question.