title: Poly(ethylene imine)-controlled calcium phosphate mineralization.
abstract: The current paper shows that poly(ethylene imine) (PEI) is an efficient template for the fabrication of spherical calcium phosphate (CaP)/polymer hybrid particles at pH values above 8. The polymer forms spherical entities, which contain one or a few CaP particles with diameters of ca. 6 nm. The samples contain up to 20 wt % polymer, which appears to be wrapped around the small CaP particles. The particles form via a mineralization-trapping pathway, where at the beginning of the precipitation small CaP particles form. Further particle growth is then prevented by precipitation of the PEI onto these particles at pH values of ca. 8. Stabilization of the particles is provided by the re-protonation of the PEI, which is adsorbed on the CaP particles, during the remainder of the mineralization process. At low pH, much larger particles form. They most likely grow via heterogeneous nucleation and growth on existing, polymer-modified CaP surfaces.
authors.affiliation: Institute of Chemistry, University of Potsdam, D-14476 Golm, Germany.
authors.forename: Andriy
authors.initials: A
authors.lastname: Shkilnyy
authors.forename: Alwin
authors.initials: A
authors.lastname: Friedrich
authors.forename: Brigitte
authors.initials: B
authors.lastname: Tiersch
authors.forename: Stefanie
authors.initials: S
authors.lastname: Schöne
authors.forename: Mabya
authors.initials: M
authors.lastname: Fechner
authors.forename: Joachim
authors.initials: J
authors.lastname: Koetz
authors.forename: Carl-Wilhelm
authors.initials: CW
authors.lastname: Schläpfer
authors.forename: Andreas
authors.initials: A
authors.lastname: Taubert
mesh_terms: D000327:Adsorption; D002130:Calcium Phosphates / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D011094:Polyethyleneimine / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water / Q000737:chemistry
chemical_list: D002130:Calcium Phosphates; D014867:Water; D011094:Polyethyleneimine