title: Polar Nature of Biomimetic Fluorapatite/Gelatin Composites: A Comparison of Bipolar Objects and the Polar State of Natural Tissue.
abstract: The correspondence of the state of alignment of macromolecules in biomimetic materials and natural tissues is demonstrated by investigating a mechanism of electrical polarity formation: An in vitro grown biomimetic FAp/gelatin composite is investigated for its polar properties by second harmonic (SHGM) and scanning pyroelectric microscopy (SPEM). Hexagonal prismatic seed crystals formed in gelatin gels represent a monodomain polar state, due to aligned mineralized gelatin molecules. Later growth stages, showing dumbbell morphologies, develop into a bipolar state because of surface recognition by gelatin functionality: A reversal of the polar alignment of macromolecules, thus, takes place close to that basal plane of the seed. In natural hard tissues (teeth and bone investigated by SPEM) and the biomimetic FAp/gelatin composite, we find a surprising analogy in view of growth-induced states of polarity: The development of polarity in vivo and in vitro can be explained by a Markov-type mechanism of molecular recognition during the attachment of macromolecules.
authors.affiliation: Department of Chemistry and Biochemistry, University of Berne , Freiestrasse 3, CH-3012 Berne, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Burgener
authors.affiliation: Department of Physics and Astronomy, Soft Matter and Biophysics Section, KU Leuven , Celestijnenlaan 200d, B-3001 Leuven, Belgium.
authors.forename: Tristan
authors.initials: T
authors.lastname: Putzeys
authors.affiliation: Department of Chemistry and Biochemistry, University of Berne , Freiestrasse 3, CH-3012 Berne, Switzerland.
authors.forename: Mazeyar Parvinzadeh
authors.initials: MP
authors.lastname: Gashti
authors.affiliation: Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Strasse 40, D-01187 Dresden, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Busch
authors.affiliation: Department of Chemistry and Biochemistry, University of Berne , Freiestrasse 3, CH-3012 Berne, Switzerland.
authors.forename: Hanane
authors.initials: H
authors.lastname: Aboulfadl
authors.affiliation: Department of Physics and Astronomy, Soft Matter and Biophysics Section, KU Leuven , Celestijnenlaan 200d, B-3001 Leuven, Belgium.
authors.forename: Michael
authors.initials: M
authors.lastname: Wübbenhorst
authors.affiliation: Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Strasse 40, D-01187 Dresden, Germany.
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Kniep
authors.affiliation: Department of Chemistry and Biochemistry, University of Berne , Freiestrasse 3, CH-3012 Berne, Switzerland.
authors.forename: Jürg
authors.initials: J
authors.lastname: Hulliger
mesh_terms: D001031:Apatites / Q000737:chemistry*; D040761:Biomimetic Materials / Q000737:chemistry*; D005780:Gelatin / Q000737:chemistry*
chemical_list: D001031:Apatites; D005780:Gelatin; C025105:fluorapatite