The metal-binding properties of rationally designed, synthetic proteins were used to prepare a series of emissive silver nanoclusters having predictable sizes and emission energies. Metal-binding a-helical coiled coils were designed to exist as peptide trimers, tetramers, and hexamers and found to uniquely bind 6, 8, and 12 Ag+ ions, respectively. Subsequent treatment with a chemical reducing agent produced a series of peptide-bound Ag-0 nanoclusters that display a strong visible fluorescence whose emission energies depend on the number of bound metal ions in excellent agreement with theory.
Morozov, Vasily A. and Ogawa, Michael Y., "Controlled Formation Of Emissive Silver Nanoclusters Using Rationally Designed Metal-binding Proteins" (2013). Chemistry Faculty Publications. 170.