Unlocking new frontiers in bioimaging: The power of FLIM-AIE integration

The frontiers of bioimaging encompass cutting-edge technologies and methodologies that enhance the visualization, analysis, and interpretation of biological structures and processes with unprecedented precision. In this context, fluorescence lifetime imaging microscopy (FLIM) has emerged as a powerful technique that enables quantitative and concentration-independent imaging by measuring the fluorescence decay time of molecular probes. Unlike intensity-based fluorescence methods, FLIM provides robust data on molecular interactions, environments, and biomarker presence, making it invaluable for bioimaging. However, its widespread adoption remains constrained by technical complexity, the high cost of instrumentation, and the underdevelopment of fluorescence lifetime probes with AIE characteristics. A promising solution to these challenges lies in aggregation-induced emission (AIE) fluorophores, which overcome issues such as aggregation-caused quenching and photobleaching. Despite their potential, AIE fluorophores have been rarely integrated with FLIM, leaving a significant gap in bioimaging research. Integrating FLIM with AIE probes could revolutionize bioimaging, enabling precise, stable, and environment-sensitive lifetime imaging for diagnostics, metabolism, and live-cell monitoring. In this perspective, we examine the potential of FLIM-AIE integration in bioimaging, highlighting its advantages, identifying key barriers, and proposing strategies to promote its use in biomedical research. We highlight the critical role of interdisciplinary collaboration, enhanced training programs, and targeted funding initiatives in accelerating innovation in the field of bioimaging.

Main text

Driving innovation in the visualization, analysis, and interpretation of biological structures and processes remains a major challenge in bioimaging. Advancements in this field have profound implications for medicine, pharmacology, nanomedicine, and molecular biology. In this context, fluorescence lifetime imaging microscopy (FLIM) has emerged as a powerful tool, offering insights into biomolecular interactions and environmental conditions. Unlike conventional fluorescence microscopy, which relies on intensity-based measurements affected by fluorophore concentration, excitation power, and photobleaching, FLIM operates independently of these variables. It measures fluorescence lifetime, the mean time fluorophores remain in the excited state before emitting photons. This parameter is sensitive to environmental factors such as pH, viscosity, and molecular binding, making FLIM a robust technique for quantitative imaging. Due to its unique ability to generate absolute, concentration-independent data, FLIM is widely applied in biomedicine. It offers advantages over intensity-based fluorescence microscopy: (1) it effectively differentiates fluorophore signals from cellular autofluorescence; (2) it is less susceptible to photobleaching, ideal for biological imaging; and (3) it reduces photodamage through pulsed excitation with short breaks while enabling precise biomarker quantification in complex systems.