Hetero‐Telechelic Dye‐Labeled Polymer for Nanoparticle Decoration

• Published in: Macromolecular rapid communications. 2009-07, Vol.30 (14), p.1274-1278
• Main Authors: Roth, Peter J., Kim, Ki‐Se, Bae, Su Hak, Sohn, Byeong‐Hyeok, Theato, Patrick, Zentel, Rudolf
• Format: Article
• Language: English
• Subjects: end group; fluorescence resonance energy transfer (FRET); nanoparticles; polymer; reversible addition fragmentation chain transfer (RAFT)
• ISSN: 1022-1336; 1521-3927
• DOI: 10.1002/marc.200900254

The synthesis of poly(methyl methacrylate) (PMMA) exhibiting one fluorescent dye (Texas Red) and one methyl disulfide end group is described. It is shown that the latter end group enabled the exchange of both oleic amine on gold nanoparticles (AuNP) and of oleic acid on CdSe/ZnS quantum dots (QD), allowing for a phase transfer of both types of nanoparticles (NP) from hexane into dimethylformamide due to the solubility provided by the PMMA chains. For AuNP, a fluorescence quenching of the dye was found due to fluorescence resonance energy transfer (FRET) from the dye to the AuNP, while QDs caused a fluorescence enhancement by FRET from the QD to the attached dyes. Due to the hetero‐telechelic geometry of the polymer, the separation between NP and dye is governed by the end‐to‐end distance of the polymer. A PMMA with a methyl disulfide and a fluorescent dye end group, synthesized by the RAFT process was used to functionalize the surfaces of gold nanoparticles and of CdSe/ZnS quantum dots. The fluorescence of the dye was quenched when tethered to gold nanoparticles, while quantum dots caused an increased dye emission.