A rational design of AIE-active fluorophore for the fingerprint optical detection

Fingerprints are one of the distinguishing characteristics of an individual, remaining unaltered throughout one's lifetime. It should be noted that fingerprints are significant and reliable evidence in various cases, such as criminal investigations, medical diagnosis, and public security. Thus, it is necessary to develop efficient techniques for fingerprints detection. Fortunately, the fluorescence emission of aggregation-induced emission (AIE) materials would increase instead of quenching upon excitation when they label fingerprints, which would clearly observe the structure of fingerprints. Herein, we devised a novel AIE-active fluorophore (NI-DB) with electron donor-pi bridge-electron acceptor (D-pi-A) structure based on the 1,8-naphthalimide. To our delight, after fingerprints fixed by cyanoacrylate glue fuming, NI-DB is capable of detecting and imaging fingerprints via its intrinsic fluorescence emission. And, with the aid of this technique, fingerprints on various object surfaces are successfully developed, suggesting the broad applicability.