Tailoring the SWIR emission of gold nanoclusters by surface ligand rigidification and their application in 3D bioimaging

Abstract

The influence of solvent polarity and surface ligand rigidification on the SWIR emission profile of gold nanoclusters with an anistropic surface was investigated. A strong enhancement of the SWIR emission...

Tailoring the NIR‐II Photoluminescence of Single Thiolated Au25 Nanoclusters by Selective Binding to Proteins**

“…However, the Au 25 -BSA complex possessed a PL lifetime of 936.1 ns, which indicates that the local environment of the Au 25 NCs in Au 25 -BSA is more rigid than that of free Au 25 pMBA 18 dispersed in water or in the presence of unbound protein. This effect was already observed earlier when AuNCs were dispersed in different media like PDMS [33] or when the organic shell was purposely rigidified. [4c] The key here is to prevent the free rotation of the surface Chemistry-A European Journal ligands, which is otherwise a possible nonradiative recombination pathway.…”

Enhanced brightness of ultra-small gold nanoparticles in the second biological window through thiol ligand shell control

“…47 This trend involves a shift in PL towards longer wavelengths through the rigidification of the surface, which limits the access of water molecules to the gold surface and reduces non-radiative processes. 35 These findings are supported by the decrease in PL lifetime, indicating more efficient energy transfer to water molecule. Furthermore, the PL emission of these emitters is dependent on the excitation wavelength, confirming the occurrence of multiple energy transfers within nanoparticles of potentially different sizes.…”

“…In this study, we prepared us-AuNPs stabilized by monothiol and short dithiol molecules that have shown promising optical properties in earlier studies 18,35 for in vivo applications. 14 Such us-AuNPs are typically obtained by combining metal salt, ligands, and a reducing agent, stirred at room temperature.…”

Luminescent Gold Nanoclusters for Bioimaging: Increasing the Ligand Complexity

“…Two years later, Le Guével et al explored the photophysical properties of (MHA/TDT) AuNCs and their application in the bioimaging field more in depth [ 80 ]. In particular, this study concerned the effect of solvent polarity on the photoluminescence properties of dual-capped (MHA/TDT) AuNCs and how the rigidity of the matrix, in which the NCs were dispersed, affects their emission.…”