Bioorthogonal reactions and AIEgen-based metabolically engineered theranostic systems

Metabolic labeling based on bioorthogonal click chemistry has transformed the way living entities are manipulated in biological environments to enable more targeted, effective, and safer thera-nostic applications. Since the first demonstrations of this strategy, many other metabolic labeling approaches have been formulated to incorporate additional functionalities, such as those based on fluorogens with aggregation-induced emission characteristic (AIE-gens), for light-up bioimaging and image-guided disease therapy. In this perspective, we discuss the emergence and development of AIEgen-based theranostic systems for bioorthogonal metabolic engineering and labeling. First, we highlight the fundamental princi-ples guiding the design of AIEgen-based bioorthogonal metabolic labeling. Next, we describe the formulation and applications of different AIEgen-based synthetic and living theranostic systems for cancer and pathogenic bacterial imaging and ablation. We then provide our outlook on the current challenges, potential op-portunities, and future research directions of this emerging field.