title: Mineralization, biodegradation, and drug release behavior of gelatin/apatite composite microspheres for bone regeneration.
abstract: Gelatin microspheres are well-known for their capacity to release growth factors in a controlled manner, but gelatin microspheres do not calcify in the absence of so-called bioactive substances that induce deposition of calcium phosphate (CaP) bone mineral. This study has investigated if CaP nanocrystals can be incorporated into gelatin microspheres to render these inert microspheres bioactive without compromising the drug releasing properties of gelatin microspheres. Incorporation of CaP nanocrystals into gelatin microspheres resulted into reduced biodegradation and drug release rates, whereas their calcifying capacity increased strongly compared to inert gelatin microspheres. The reduced drug release rate was correlated to the reduced degradation rate as caused by a physical cross-linking effect of CaP nanocrystals dispersed in the gelatin matrix. Consequently, these composite microspheres combine beneficial drug-releasing properties of organic gelatin with the calcifying capacity of a dispersed CaP phase.
authors.affiliation: Department of Biomaterials, Radboud University Nijmegen Medical Center, Philips van Leydenlaan 25, Nijmegen, The Netherlands. s.leeuwenburgh@dent.umcn.nl
authors.forename: Sander C G
authors.initials: SC
authors.lastname: Leeuwenburgh
authors.forename: Junichiro
authors.initials: J
authors.lastname: Jo
authors.forename: Huanan
authors.initials: H
authors.lastname: Wang
authors.forename: Masaya
authors.initials: M
authors.lastname: Yamamoto
authors.forename: John A
authors.initials: JA
authors.lastname: Jansen
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tabata
mesh_terms: D001031:Apatites / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology; D001826:Body Fluids / Q000737:chemistry; D001861:Bone Regeneration / Q000187:drug effects; D018786:Bone Substitutes / Q000008:administration & dosage / Q000737:chemistry* / Q000494:pharmacology; D002113:Calcification, Physiologic / Q000187:drug effects; D003432:Cross-Linking Reagents; D004337:Drug Carriers / Q000737:chemistry*; D016222:Fibroblast Growth Factor 2 / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology; D005780:Gelatin / Q000737:chemistry*; D006801:Humans; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D008954:Models, Biological; D053758:Nanoparticles; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology; D012995:Solubility; D013499:Surface Properties
chemical_list: D001031:Apatites; D018786:Bone Substitutes; D003432:Cross-Linking Reagents; D004337:Drug Carriers; D011994:Recombinant Proteins; D016222:Fibroblast Growth Factor 2; D005780:Gelatin