title: Bovine Serum Albulmin Protein-Templated Silver Nanocluster (BSA-Ag13): An Effective Singlet Oxygen Generator for Photodynamic Cancer Therapy.
abstract: This paper reports a novel synthesis approach of bovine serum albumin (BSA) protein-templated ultrasmall (<2 nm) Ag nanocluster (NC) with strong singlet oxygen generation capacity for photodynamic therapy (PDT). An atomically precise BSA-Ag13NC (i.e., 13 Ag atoms per cluster) is successfully synthesized for the first time by using NaOH-dissolved NaBH4solution as the controlling reducing agent. The ubiquitous size of BSA-Ag13NC results in unique behaviors of its photoexcited states as characterized by the ultrafast laser spectroscopy using time-correlated single photon counting and transient absorption techniques. In particular, triply excited states can be largely present in the excited BSA-Ag13NC and readily sensitized molecular oxygen to produce singlet oxygen (1O2) with a high quantum efficiency (≈1.26 using Rose Bengal as a standard). This value is much higher than its Au analogue (i.e., ≈0.07 for BSA-Au25NC) and the commonly available photosensitizers. Due to the good cellular uptake and inherent biocompatibility imparted by the surface protein, BSA-Ag13NC can be applied as an effective PDT agent in generating1O2to kill cancer cell as demonstrated in this study.
authors.affiliation: Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, #08-03, Innovis, 138634, Singapore.
authors.forename: Yong
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, #08-03, Innovis, 138634, Singapore.
authors.forename: Junlong
authors.initials: J
authors.lastname: Geng
authors.affiliation: Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, #08-03, Innovis, 138634, Singapore.
authors.forename: Edward Yong Xi
authors.initials: EY
authors.lastname: Ong
authors.affiliation: Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, #08-03, Innovis, 138634, Singapore.
authors.forename: Vijila
authors.initials: V
authors.lastname: Chellappan
authors.affiliation: Institute of Materials Research and Engineering, The Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, #08-03, Innovis, 138634, Singapore. tanyn@imre.a-star.edu.sg.
authors.forename: Yen Nee
authors.initials: YN
authors.lastname: Tan
mesh_terms: D000818:Animals; D002417:Cattle; D045744:Cell Line, Tumor; D006801:Humans; D061986:MCF-7 Cells; D053758:Nanoparticles / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D010778:Photochemotherapy / Q000379:methods; D017785:Photons; D017319:Photosensitizing Agents / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D026082:Singlet Oxygen / Q000737:chemistry*
chemical_list: D017319:Photosensitizing Agents; D026082:Singlet Oxygen; D012710:Serum Albumin, Bovine; D012834:Silver; D010100:Oxygen
keywords: photodynamic therapy; photoluminescence; silver nanoclusters; singlet oxygen; triplet state