High photoluminescence of shortwave infrared-emitting anisotropic surface charged gold nanoclusters

Abstract

Incorporating anisotropic surface charges on atomically precise gold nanoclusters led to a intense shortwave infrared photoluminescence exceeding 1100 nm with QY up to 6.1%.

High-Resolution Shortwave Infrared Imaging of Vascular Disorders Using Gold Nanoclusters

“…The images in Figure 1e show an up to 12-fold more intense signal for AuMHA/TDT using long pass filters above 1250 nm confirming the superior brightness of our new Au NCs in water as compared to the existing SWIR-emissive ones. We estimated then a quantum yield at ∼6%, in the same range as Au NCs stabilized by both ligands mercaptohexanoic acid (MHA) and dithiol hexa(ethyleneglycol) that we previously prepared 11 . This QY is higher than the others Au NCs already in the literature for Au 25 SG 18…”

“…(0.67%) 14 , AuMHA (0.9%) 11 , and AuZw (3.8%) 8 . The PL features of AuMHA/TDT remain unchanged in water and in the presence of 10% serum ( Figure S6).…”

“…After 5 min, 150 µL NaBH 4 (20 mM in 0.2 M NaOH) was introduced dropwise under mild stirring and kept under stirring at 350 rpm for 8 hours. Purification of the AuMHA/TDT on 3 kDa cut-off filter column (Amicon) were repeated 3 times to stop the reaction and sols were kept stored in the fridge before characterization.The Au NCs, Au MHA11 , AuZwMe 28 and Au 25 SG18 22 were synthesized following the protocols described in the literature.ASSOCIATED CONTENTSSupporting Information contains: physico-chemical and photophysical of Au NCs; cytotoxicity and additional in vivo experiments in mice are available from American Chemical Society or from the author. le-guevel@univ-grenoble-alpes.fr 0000-0003-3634-7762 *jean-luc.coll@univ-grenoble-alpes.fr 0000-0002-2453-3552 l'Energie Atomique et aux Energies Alternatives (CEA, DRF/IRIG), the University Grenoble Alpes (UGA, BCI), the Fondation pour la Recherche Médicale (FRM).…”

Aza-BODIPY: A New Vector for Enhanced Theranostic Boron Neutron Capture Therapy Applications

“…A dedicated confocal We recently reported the use of a B-functionalized aza-BODIPY emitting in the SWIR region and accumulating in tumors via EPR effect (Enhanced permeability and retention effect) with high and prolonged Tumor/Healthy Muscle ratio (between 5 and 30, from 24 to 168 h post-injection) without the need of tethering vector [29]. SWIR fluorophores enable to reach a penetration depth of 1 to 10 mm with increased resolution of the images as compared to those obtained with NIR-I probes [42,43]. Here, such aza-BODIPY was used to vectorize the small 10 B-BSH molecule at the tumor site while benefitting from the imaging properties of the fluorophore for theranostic applications.…”

Origin of the Photoluminescence of Metal Nanoclusters: From Metal-Centered Emission to Ligand-Centered Emission

“…Au and Ag NCs in particular have attracted tremendous interest because of their wide applications in single-molecule studies, sensing, biolabeling, catalysis, and biological fluorescence imaging [7][8][9][10][11][12][13][14][15][16]. The physical and chemical properties of metal nanoclusters (MNCs) are highly dependent on their size, shape, composition, and even assembly architecture [17][18][19][20]. These clusters are composed of a few to hundreds of atoms with a size approaching the Fermi wavelength of an electron (~0.5 nm for Au and Ag), and they possess discrete molecular-like electronic energy band structures, resulting in intense light absorption and emission.…”