"Shine & Click" Photo-Induced Interfacial Unmasking of Strained Alkynes on Small Water-Soluble Gold Nanoparticles.
Wilson LuoPierangelo GobboChristopher D McNittDewey A SuttonVladimir V PopikMark S WorkentinPublished in: Chemistry (Weinheim an der Bergstrasse, Germany) (2016)
In this study, we report the design, synthesis, and characterization of small 3 nm water soluble gold nanoparticles (AuNPs) that feature cyclopropenone-masked strained alkyne moieties capable of undergoing interfacial strain-promoted cycloaddition (i-SPAAC) with azides after exposure to UV-A light. A strained alkyne precursor was incorporated onto AuNPs by direct ligand exchange of a thiol-modified cyclopropenone-masked dibenzocyclooctyne (photoDIBO) ligand. These photoDIBO-AuNPs were characterized by 1 H NMR, IR, and UV/Vis spectroscopy, as well as transmission electron microscopy (TEM) and thermogravimetric analysis (TGA), and the extent of modification was quantified. Upon irradiation with UV-A light, photoDIBO-AuNPs underwent efficient and quantitative regeneration of the parent strained alkyne by photochemical decarbonylation to afford DIBO-derivatized AuNPs. DIBO-AuNPs were found to react cleanly and rapidly (k=5.3×10-2 m-1 s-1 ) by an interfacial strain-promoted alkyne-azide cycloadditon (i-SPAAC) with benzyl azide, which served as a simple model system. Furthermore, DIBO-AuNPs were reacted with various azides and a nitrone (interfacial strain-promoted alkyne-nitrone cycloaddition, i-SPANC) to showcase the generality of this approach for the facile modification of AuNP surfaces and their properties. The cyclopropenone-based photo-triggered click chemistry at the interface of water-soluble AuNPs offers exciting opportunities for the atom-by-atom control and assembly of functional materials for applications in materials and biomaterials science as well as in chemical biology.
Keyphrases
- water soluble
- gold nanoparticles
- electron transfer
- ionic liquid
- molecular dynamics simulations
- high resolution
- stem cells
- reduced graphene oxide
- machine learning
- public health
- magnetic resonance
- electron microscopy
- cystic fibrosis
- pseudomonas aeruginosa
- photodynamic therapy
- deep learning
- radiation therapy
- quantum dots
- staphylococcus aureus
- aqueous solution