1. Department of Polymer Chemistry and Biomaterials, MIRA Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands;2. Department of Biomolecular Nanotechnology, MESA+ Institute for Nanotechnology, University of Twente, P. O. Box 217, 7500 AE Enschede, The Netherlands
Abstract:
Branched poly(methoxy‐PEG acrylate) and thermally responsive poly(methoxy‐PEG acrylate)‐block‐poly(N‐isopropylacrylamide) are synthesized by RAFT polymerization. After reduction, these polymers are fluorescently labeled by reacting the free thiol groups with N‐(5‐fluoresceinyl)maleimide. As shown by DLS, the labeled copolymer poly(methoxy‐PEG acrylate)‐block‐poly(N‐isopropylacrylamide) forms nanoparticles at body temperature (37 °C) due to the presence of the thermosensitive poly(N‐isopropylacrylamide). These materials were used as bioprobes for imaging HUVECs in vitro and chick embryo CAM in vivo. Both labeled polymer and nanoparticles are biocompatible and can be used as efficient fluorescent bioprobes.