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Title: Luminescent Quantum Dots Stabilized by N-Heterocyclic Carbene Polymer Ligands
We designed a novel multicoordinating ligand based on the N-heterocyclic carbene (NHC) anchoring molecules and applied them for stabilizing luminescent quantum dots in aqueous media. The ligand is synthesized via nucleophilic addition reaction between amine-appended imidazole/poly(ethylene glycol) compounds and poly(isobutylene-alt-maleic anhydride) (PIMA), followed by carbene generation. We find that these NHC-based polymers exhibit fast and robust coordinating affinity to CdSe QDs overcoated with ZnS shells. The removal of hydrophobic coating and the generation of carbene are demonstrated by 1H NMR spectroscopy. 13C NMR spectroscopy confirms the existence of carbene-Zn complexes which is crucial for binding transition-metals on QD surfaces. These QDs exhibit absorption and emission features with little to no change before and after cap exchange, and their PL intensity is increased under light exposure. Excellent colloidal stability of these QD samples is observed in a wide range of competitive conditions over long period of time. Agarose gel electrophoresis indicates that the polymer coating imparts QDs with good compatibility in different aqueous buffers, and it prevents protein adsorption.  more » « less
Award ID(s):
2005079 1508501
PAR ID:
10327888
Author(s) / Creator(s):
; ; ; ; ; ;
Corporate Creator(s):
Publisher / Repository:
ACS
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
143
Issue:
4
ISSN:
0002-7863
Page Range / eLocation ID:
1873 to 1884
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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