Highly Bright Self-Assembled Copper Nanoclusters: A Novel Photoluminescent Probe for Sensitive Detection of Histamine

In this work, highly photoluminescent (PL) self-assembled copper nanoclusters (Cu NCs) capable of rapid, sensitive, and selective detection of histamine were developed. Cu NCs were synthesized in facile conditions by using 2,3,5,6-tetrafluorothiophenol (TFTP) as both the reducing agent and the protecting ligand, which exhibited intense saffron yellow (590 nm) PL via self-assembled induced emission (SAIE), and the absolute quantum yield (QY) of assembly was as high as 43.0%. The size, electronic states, and morphologies of the assembled nanoribbons were characterized, and the geometric structure and spectral properties of the Cu NCs were investigated by theoretical study. Furthermore, the mechanism of the excellent sensing performance of Cu NCs toward histamine was demonstrated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and energy dispersive X-ray analysis (EDX). With this sensing system, the amount of histamine in fish, shrimp, and red wine were analyzed, and experiment results verified the application of the sensor. Importantly, the luminescent test strips based on Cu NCs were fabricated for colorimetric detection of histamine in foods. This proposed technique may provide an alternative to traditional methods for histamine detection.