Article Cite This: Chem. Mater. 2017, 29, 9416-9428
pubs.acs.org/cm
Surface-Engineered Cationic Nanocrystals Stable in Biological Buffers and High Ionic Strength Solutions Ryan M. Dragoman,† Marcel Grogg,§ Maryna I. Bodnarchuk,†,‡ Peter Tiefenboeck,∥ Donald Hilvert,§ Dmitry N. Dirin,*,† and Maksym V. Kovalenko*,†,‡ †
Institute of Inorganic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland Laboratory of Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland ‡ Laboratory for Thin Films and Photovoltaics, Empa-Swiss Federal Laboratories for Materials Science and Technology, CH-8600 Dübendorf, Switzerland ∥ Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zürich, CH-8093 Zürich, Switzerland §
S Supporting Information *
ABSTRACT: Progress in colloidal synthesis in the last two decades has enabled high-quality semiconductor, plasmonic, and magnetic nanocrystals (NCs). As synthesized, these NCs are usually capped with long-chain apolar ligands. Postsynthetic surface functionalization is required for rendering such NCs colloidally stable in polar media such as water. However, unlike small anionic molecules and polymeric coatings, producing positively charged stable NCs, especially at high ionic strengths, has remained challenging. Here, we present a general approach to achieve aqueously stable cationic NCs using a set of small (
