Fluorescent gold nanoclusters (AuNCs) are envisaged as a novel type of fluorophores. This work reports on the first comparative study investigating the effect of presence/absence/abundance of fatty acids (namely palmitic acid, PA) or other substances (like glycoproteins and globulins) in the protein (bovine serum albumin, BSA) on synthesis and properties of the final AuNCs. The most popular template (BSA) and microwave (MW)-assisted synthesis of AuNCs have been intentionally chosen. Our results clearly demonstrate that the fluorescent characteristics (i.e., fluorescence lifetime and quantum yield) are affected by the fatty acids and/or other substances. Importantly, the as-prepared AuNCs are biocompatible, as determined by Alamar Blue assay performed on Hep G2 cell line.

Department of Biophysics Faculty of Science Palacký University Olomouc 17 Listopadu 12 771 46 Olomouc Czech Republic

Department of Experimental Physics Faculty of Science Palacký University Olomouc 17 Listopadu 12 771 46 Olomouc Czech Republic

Department of Science and Research Faculty of Health Studies Technical University of Liberec Studentska 1402 2 461 17 Liberec Czech Republic

Institute for Clinical and Experimental Medicine Videnska 9 140 21 Prague Czech Republic

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Maturing conditions of bimetallic nanocomposites as a new factor influencing Au-Ag synergism and impact of Cu(II) and/or Fe(III) on luminescence

Facile One-Pot Green Synthesis of Magneto-Luminescent Bimetallic Nanocomposites with Potential as Dual Imaging Agent

Evidence of Au(II) and Au(0) States in Bovine Serum Albumin-Au Nanoclusters Revealed by CW-EPR/LEPR and Peculiarities in HR-TEM/STEM Imaging