title: Enhanced emission and its switching in fluorescent organic nanoparticles.
abstract: A new class of organic nanoparticles (CN-MBE nanoparticles) with a mean diameter of ca. 30-40 nm, which exhibit a strongly enhanced fluorescence emission, were prepared by a simple reprecipitation method. CN-MBE (1-cyano-trans-1,2-bis-(4'-methylbiphenyl)ethylene) is very weakly fluorescent in solution, but the intensity is increased by almost 700 times in the nanoparticles. Enhanced emission in CN-MBE nanoparticles is attributed to the synergetic effect of intramolecular planarization and J-type aggregate formation (restricted excimer formation) in nanopaticles. On/off fluorescence switching for organic vapor was demonstrated with CN-MBE nanoparticles.
authors.affiliation: School of Materials Science & Engineering, Seoul National University, Seoul, 151-744, Korea.
authors.forename: Byeong-Kwan
authors.initials: BK
authors.lastname: An
authors.forename: Soon-Ki
authors.initials: SK
authors.lastname: Kwon
authors.forename: Sang-Don
authors.initials: SD
authors.lastname: Jung
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Park
mesh_terms: D001713:Biphenyl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D008968:Molecular Conformation; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D013050:Spectrometry, Fluorescence / Q000379:methods; D013056:Spectrophotometry, Ultraviolet
chemical_list: C472179:1-cyano-1,2-bis-(4'-methylbiphenyl)ethylene; D001713:Biphenyl Compounds; D005456:Fluorescent Dyes