Metal nanoparticles offer great opportunities for molecular electronics, catalysis, and medicinal applications. The properties of nanoparticles depend strongly on their size and shape, which is controlled by the addition of additives during their formation. However, the controlled synthesis of mono-disperse nanoparticles in defined sizes is challenging and little is known about the correlation between the molecular structure of the additive and the resulting nanoparticles.
We develop peptides as additives for the size-controlled generation of noble metal nanoparticles. In addition, we aim at understanding how the molecular features of the additive control nanoparticle formation. To tackle these goals we use a combination of combinatorial chemistry and rational design. Colorimetric combinatorial assays with split-and-mix libraries allowed for the identification of tripeptides that control the formation of mono-disperse, water-soluble Ag-, Pd-, Pt-, and AuNPs in defined sizes. Structure-activity relationship studies revealed a specific role of each amino acid for the formation and stabilization of the nanoparticles. Furthermore, the use of functionalized oligoprolines as conformationally rigid, reducing, and stabilizing agents allowed for the first time to establish a direct correlation between the molecular dimensions of the additive and the nanoscopic dimensions of the formed metal nanoparticles.
These findings open intriguing prospects for the design of additives to develop size-controlled and functionalized metal NPs for catalysis and medicinal applications.
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Angew. Chem. Int. Ed. 2016, 55, 8542–8545
- G. Upert, F. Bouillère, H. Wennemers, "Correlating Molecular with Nanoscopic Dimensions - Oligoprolines as Scaffolds for the Formation of Ag-Nanoparticles in Defined Sizes"
Angew. Chem. Int. Ed., 2012, 51, 4231–4234
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