A single-scaffold AIE probe for cross-context fluorescence: from lipid droplet imaging to information concealment and...

Lipid droplets (LDs) are dynamic organelles that play important roles in lipid storage and metabolism and are involved in a variety of pathological processes. Fluorescent probes with high photostability are useful for tracking LDs over extended periods. Here, we developed a triphenylamine-based donor-acceptor aggregation-induced emission (AIE) fluorophore, TBI, for LD imaging and latent fingerprint visualization. The twisted structure of TBI promotes aggregation-induced emission and suppresses photobleaching, allowing its fluorescence to remain stable during prolonged imaging. TBI showed a preference for intracellular LDs and enabled visualization of LD morphology and dynamics in living cells and zebrafish larvae. TBI could also be prepared as a fluorescent ink for information encryption and anti-counterfeiting. Moreover, it revealed latent fingerprints with clear ridge patterns on various common substrates, allowing both level-2 details and finer level-3 features to be resolved. Thus, TBI provides a compact AIE molecular scaffold that connects LD imaging with fluorescence-based fingerprint visualization and expands the use of AIE fluorophores in biological and forensic applications.