Engineering J-Aggregated Organic Dyes for Enhanced Phototheranostics

Precision phototheranostics of malignant tumors has become a prominent research focus in the field of biomedicine. However, conventional organic dyes are severely limited in their efficacy for tumor theranostics due to the aggregation-caused quenching (ACQ) effect. By precisely regulating the stacking mode, J-aggregation effectively suppresses ACQ and endows organic dyes with unique photophysical properties, including a red-shifted spectrum, an enhanced molar extinction coefficient, and improved efficiency in photothermal conversion and reactive oxygen species generation. Consequently, it has emerged as an effective strategy to advance tumor phototheranostics. Based on the exciton-coupling model, this Article elucidates the intrinsic relationship between molecular stacking modes and the theranostic performance of organic dyes. It systematically summarizes recent progress in the application of J-aggregates to tumor fluorescence/photoacoustic imaging, photothermal therapy, photodynamic therapy, and multimodal theranostics. Furthermore, current key challenges and future research directions for J-aggregated organic dyes are discussed. This Article aims to provide theoretical insights and design principles for the rational development of novel J-aggregated organic dyes and the construction of precise tumor theranostics systems, thereby facilitating further advancement and clinical translation of tumor phototheranostics.