Luminescent Copper Nanoclusters as a Specific Cell-Imaging Probe and a Selective Metal Ion Sensor

• Published in: Journal of physical chemistry. C 2015-10, Vol.119 (43), p.24657-24664
• Main Authors: Das, Nirmal Kumar, Ghosh, Subhadip, Priya, Amulya, Datta, Sunando, Mukherjee, Saptarshi
• Format: Article
• Language: English
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/acs.jpcc.5b08123

Copper nanoclusters (CuNCs) exhibit a high tendency to undergo oxidation particularly at the subnanometer size regime. In the light of overcoming this bottleneck, we have been successful in developing tripeptide (glutathione, GSH) templated CuNCs which show high biocompatibility and stability, in spite of being ultrafine in size. These blue-emitting CuNCs possess very promising optical features such as significant quantum yield (QY) and excellent photostability. Our cell-imaging studies reveal that the CuNCs localize primarily in nuclear membranes of the different cancerous (Hela, MDAMB-231, and A549) cells, and the cell viability assay conclusively established their nontoxic nature. Apart from their biological significances, these CuNCs also illustrate their ability to serve as a metal ion sensor, selectively detecting Fe3+ ions in solution at the nanomolar concentration regime. This unique luminescent property of the NCs will enable them to serve as label-free and versatile probes having several biological and analytical applications.