Violet ZnSe/ZnS as an Alternative to Green CdSe/ZnS in Nanocrystal−Fluorescent Protein FRET Systems

• Published in: Bioconjugate chemistry Vol. 20; no. 6; pp. 1237 - 1241
• Main Authors: Hering, Vitor R, Faulin, Tanize E. S, Triboni, Eduardo R, Rodriguez, Silvio D, Bernik, Delia L, Schumacher, Robert I, Mammana, Victor P, Faljoni-Alario, Adelaide, Abdalla, Dulcineia S. P, Gibson, Gary, Politi, Mário J
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 17.06.2009
• Subjects: Anisotropy; Biochemistry; Color; Fluorescence; Fluorescence Polarization; Fluorescence Resonance Energy Transfer; Luminescence; Luminescent Proteins - chemistry; Luminescent Proteins - metabolism; Nanocrystals; Nanoparticles - chemistry; Proteins; Selenium Compounds - chemistry; Selenium Compounds - metabolism; Zinc Compounds - chemistry; Zinc Compounds - metabolism; Zinc Sulfate - chemistry; Zinc Sulfate - metabolism
• ISSN: 1043-1802; 1520-4812
• DOI: 10.1021/bc9001085

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.