title: Sodium cholate-templated blue light-emitting Ag subnanoclusters: in vivo toxicity and imaging in zebrafish embryos.
abstract: We report a novel green chemical approach for the synthesis of blue light-emitting and water-soluble Ag subnanoclusters, using sodium cholate (NaC) as a template at a concentration higher than the critical micelle concentration (CMC) at room temperature. However, under photochemical irradiation, small anisotropic and spherically shaped Ag nanoparticles (3-11 nm) were obtained upon changing the concentration of NaC from below to above the CMC. The matrix-assisted laser desorption ionization time-of-flight and electrospray ionization mass spectra showed that the cluster sample was composed of Ag4 and Ag6. The optical properties of the clusters were studied by UV-visible and luminescence spectroscopy. The lifetime of the synthesized fluorescent Ag nanoclusters (AgNCs) was measured using a time-correlated single-photon counting technique. High-resolution transmission electron microscopy was used to assess the size of clusters and nanoparticles. A protocol for transferring nanoclusters to organic solvents is also described. Toxicity and bioimaging studies of NaC templated AgNCs were conducted using developmental stage zebrafish embryos. From the survival and hatching experiment, no significant toxic effect was observed at AgNC concentrations of up to 200 μL/mL, and the NC-stained embryos exhibited blue fluorescence with high intensity for a long period of time, which shows that AgNCs are more stable in living system.
authors.affiliation: Department of Polymer Science, University of Madras , Guindy Campus, Chennai 600025, Tamil Nadu, India.
authors.forename: Shanmugam
authors.initials: S
authors.lastname: Chandirasekar
authors.forename: Chandramouli
authors.initials: C
authors.lastname: Chandrasekaran
authors.forename: Thangavel
authors.initials: T
authors.lastname: Muthukumarasamyvel
authors.forename: Ganapasam
authors.initials: G
authors.lastname: Sudhandiran
authors.forename: Nagappan
authors.initials: N
authors.lastname: Rajendiran
mesh_terms: D000818:Animals; D004625:Embryo, Nonmammalian / Q000737:chemistry* / Q000187:drug effects / Q000528:radiation effects; D005453:Fluorescence; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity; D057054:Molecular Imaging / Q000295:instrumentation*; D012834:Silver / Q000737:chemistry* / Q000633:toxicity; D020358:Sodium Cholate / Q000737:chemistry* / Q000633:toxicity; D015027:Zebrafish / Q000196:embryology*
chemical_list: D012834:Silver; D020358:Sodium Cholate
keywords: imaging; irradiation; luminescence; silver; subnanocluster; zebrafish