Ultrabright Fluorescent Polymeric Nanoparticles Made from a New Family of BODIPY Monomers

• Published in: Macromolecules Vol. 46; no. 13; pp. 5167 - 5176
• Main Authors: Grazon, Chloé, Rieger, Jutta, Méallet-Renault, Rachel, Charleux, Bernadette, Clavier, Gilles
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 09.07.2013
• Subjects: Applied sciences; Chemical Sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polymers; Polymers with particular properties; Preparation, kinetics, thermodynamics, mechanism and catalysts; Organic trithiocarbonate; Fluorine containing copolymer; Emulsion copolymerization; Nanoparticle; Fluorescence; Ethylene oxide copolymer; Experimental study; Boron copolymer; Monodispersed polymer; Chain transfer; Fluorescent material; Optical properties; Preparation; Acrylate copolymer; Nitrogen boron heterocycle; Methacrylate copolymer; Radical copolymerization; Aqueous dispersion; Styrene copolymer; time-resolved spectroscopy; copolymerization; microstructure; fluorescence; spectroscopy; miniemulsion; controlled radical polymerization; RAFT
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/ma400590q

Four novel BODIPY derivatives (π-) functionalized by different polymerizable groups, styrene (S), phenyl acrylate (PhA), ethyl methacrylate (EtMA) and ethyl acrylate (EtA) have been synthesized. Following a formerly established one-pot RAFT miniemulsion polymerization process ( Grazon Macromol. Rapid Commun. 2011, 32, 699−705 ), the fluorophores were copolymerized in a controlled way at 2.6 mol % with styrene in water. On the basis of the polymerization-induced self-assembly (PISA) principle, the copolymers assembled during their formation into fluorescent nanoparticles. The distribution of the fluorescent monomers along the polymer backbone was monitored by kinetic studies of the copolymerization reaction. Fluorescent stationary and time-resolved spectroscopy was then performed on both the monomers and the nanoparticles (NPs) and the observed differences are discussed in view of the distribution of the fluorescent monomers in the polymer chain. With two of the novel fluorescent monomers (πS and πPhA), the brightness of the NPs could be significantly improved (by a factor 2) compared to particles comprising the other BODIPY monomers. The obtained particles were 200 to 2000 times brighter than usual quantum dots and 40 to 300 times brighter than most of the fluorescent polymeric nanoparticles reported in the literature.