title: Violet ZnSe/ZnS as an alternative to green CdSe/ZnS in nanocrystal-fluorescent protein FRET systems.
abstract: Fluorescent proteins from the green fluorescent protein family strongly interact with CdSe/ZnS and ZnSe/ZnS nanocrystals at neutral pH. Green emitting CdSe/ZnS nanocrystals and red emitting fluorescent protein dTomato constitute a 72% efficiency FRET system with the largest alteration of the overall photoluminescence profile, following complex formation, observed so far. The substitution of ZnSe/ZnS for CdSe/ZnS nanocrystals as energy donors enabled the use of a green fluorescent protein, GFP5, as energy acceptor. Violet emitting ZnSe/ZnS nanocrystals and green GFP5 constitute a system with 43% FRET efficiency and an unusually strong sensitized emission. ZnSe/ZnS-GFP5 provides a cadmium-free, high-contrast FRET system that covers only the high-energy part of the visible spectrum, leaving room for simultaneous use of the yellow and red color channels. Anisotropic fluorescence measurements confirmed the depolarization of GFP5 sensitized emission.
authors.affiliation: Department of Biochemistry, Chemistry Institute, University of Sao Paulo, Sao Paulo, SP 05513-970, Brazil. vrhering@uol.com.br
authors.forename: Vitor R
authors.initials: VR
authors.lastname: Hering
authors.forename: Tanize E S
authors.initials: TE
authors.lastname: Faulin
authors.forename: Eduardo R
authors.initials: ER
authors.lastname: Triboni
authors.forename: Silvio D
authors.initials: SD
authors.lastname: Rodriguez
authors.forename: Delia L
authors.initials: DL
authors.lastname: Bernik
authors.forename: Robert I
authors.initials: RI
authors.lastname: Schumacher
authors.forename: Victor P
authors.initials: VP
authors.lastname: Mammana
authors.forename: Adelaide
authors.initials: A
authors.lastname: Faljoni-Alario
authors.forename: Dulcineia S P
authors.initials: DS
authors.lastname: Abdalla
authors.forename: Gary
authors.initials: G
authors.lastname: Gibson
authors.forename: Mário J
authors.initials: MJ
authors.lastname: Politi
mesh_terms: D003116:Color; D005454:Fluorescence Polarization; D031541:Fluorescence Resonance Energy Transfer; D008164:Luminescent Proteins / Q000737:chemistry* / Q000378:metabolism; D053758:Nanoparticles / Q000737:chemistry*; D018036:Selenium Compounds / Q000737:chemistry* / Q000378:metabolism; D017967:Zinc Compounds / Q000737:chemistry* / Q000378:metabolism; D019287:Zinc Sulfate / Q000737:chemistry* / Q000378:metabolism
chemical_list: D008164:Luminescent Proteins; D018036:Selenium Compounds; D017967:Zinc Compounds; D019287:Zinc Sulfate; C044696:zinc selenide