title: Highly stable biocompatible inorganic nanoparticles by self-assembly of triblock-copolymer ligands.
abstract: A novel type of ligand for biofunctionalization of nanoparticles is presented that comprises tailor-made triblock-copolymers consisting of a polyethylene imine binding block, a hydrophobic polycaprolactone and a terminal functionalized polyethelene oxide block. Phase transfer to water occurs simply by ligand and water addition and removal of the organic solvents. It is shown that the intermediate polycaprolacton block favors the attachment to the particle surface and shields the binding groups effectively from the solution. As a consequence, the particles exhibit an outstanding stability in various aqueous media for biological studies and give easy access to specific coupling reactions at the terminal end groups of the polyethylene oxide block. Controlling the ligand exchange parameters leads to self-assembly to either individual encapsulated nanoparticles or to multifunctional nanobeads.
authors: Institute of Physical Chemistry, University of Hamburg, Grindelallee 117, 20146 Hamburg, Germany.
authors: Elmar
authors: E
authors: Pöselt
authors: Steffen
authors: S
authors: Fischer
authors: Stephan
authors: S
authors: Foerster
authors: Horst
authors: H
authors: Weller
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis; D002214:Capsules / Q000737:chemistry; D004355:Drug Stability; D007097:Imines; D008024:Ligands; D053758:Nanoparticles / Q000737:chemistry*; D011091:Polyesters; D011092:Polyethylene Glycols; D011095:Polyethylenes; D011108:Polymers / Q000138:chemical synthesis*; D012995:Solubility
chemical_list: D001672:Biocompatible Materials; D002214:Capsules; D007097:Imines; D008024:Ligands; D011091:Polyesters; D011095:Polyethylenes; D011108:Polymers; C505405:poly(ethylene imine); C016240:polycaprolactone; D011092:Polyethylene Glycols