title: Generation of composites for bone tissue-engineering applications consisting of gellan gum hydrogels mineralized with calcium and magnesium phosphate phases by enzymatic means.
abstract: Mineralization of hydrogels, desirable for bone regeneration applications, may be achieved enzymatically by incorporation of alkaline phosphatase (ALP). ALP-loaded gellan gum (GG) hydrogels were mineralized by incubation in mineralization media containing calcium and/or magnesium glycerophosphate (CaGP, MgGP). Mineralization media with CaGP:MgGP concentrations 0.1:0, 0.075:0.025, 0.05:0.05, 0.025:0.075 and 0:0.1 (all values mol/dm3, denoted A, B, C, D and E, respectively) were compared. Mineral formation was confirmed by IR and Raman, SEM, ICP-OES, XRD, TEM, SAED, TGA and increases in the the mass fraction of the hydrogel not consisting of water. Ca was incorporated into mineral to a greater extent than Mg in samples mineralized in media A-D. Mg content and amorphicity of mineral formed increased in the order A < B < C < D. Mineral formed in media A and B was calcium-deficient hydroxyapatite (CDHA). Mineral formed in medium C was a combination of CDHA and an amorphous phase. Mineral formed in medium D was an amorphous phase. Mineral formed in medium E was a combination of crystalline and amorphous MgP. Young's moduli and storage moduli decreased in dependence of mineralization medium in the order A > B > C > D, but were significantly higher for samples mineralized in medium E. The attachment and vitality of osteoblastic MC3T3-E1 cells were higher on samples mineralized in media B-E (containing Mg) than in those mineralized in medium A (not containing Mg). All samples underwent degradation and supported the adhesion of RAW 264.7 monocytic cells, and samples mineralized in media A and B supported osteoclast-like cell formation. Copyright © 2014 John Wiley & Sons, Ltd.
authors.affiliation: Polymer Chemistry and Biomaterials (PBM) Group, Department of Organic Chemistry, Ghent University, Belgium.
authors.forename: Timothy E L
authors.initials: TE
authors.lastname: Douglas
authors.affiliation: Department of Biomaterials, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Krakow, Poland.
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Krawczyk
authors.affiliation: Department of Biomaterials, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Krakow, Poland.
authors.forename: Elzbieta
authors.initials: E
authors.lastname: Pamula
authors.affiliation: Department of Basic Medical Science - Histology Group, Ghent University, Belgium.
authors.forename: Heidi A
authors.initials: HA
authors.lastname: Declercq
authors.affiliation: Centre for Microsystems Technology (CMST), ELIS, Imec, Ghent, Belgium.
authors.forename: David
authors.initials: D
authors.lastname: Schaubroeck
authors.affiliation: Department of Biomaterials, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Krakow, Poland.
authors.forename: Miroslaw M
authors.initials: MM
authors.lastname: Bucko
authors.affiliation: Department of Analytical Chemistry, Ghent University, Belgium.
authors.forename: Lieve
authors.initials: L
authors.lastname: Balcaen
authors.affiliation: Department of Inorganic Chemistry, COMOC, Ghent University, Belgium.
authors.forename: Pascal
authors.initials: P
authors.lastname: Van Der Voort
authors.affiliation: Department of Materials Science and Engineering, Zwijnaarde, Belgium.
authors.forename: Vitaliy
authors.initials: V
authors.lastname: Bliznuk
authors.affiliation: Department of Basic Medical Science - Biomaterials Group, Ghent University, Belgium.
authors.forename: Natasja M F
authors.initials: NM
authors.lastname: van den Vreken
authors.affiliation: Polymer Chemistry and Biomaterials (PBM) Group, Department of Organic Chemistry, Ghent University, Belgium.
authors.forename: Mamoni
authors.initials: M
authors.lastname: Dash
authors.affiliation: Department of Materials Science and Engineering, Institute of Biomaterials (WW7), University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Detsch
authors.affiliation: Department of Materials Science and Engineering, Institute of Biomaterials (WW7), University of Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Aldo R
authors.initials: AR
authors.lastname: Boccaccini
authors.affiliation: Department of Analytical Chemistry, Ghent University, Belgium.
authors.forename: Frank
authors.initials: F
authors.lastname: Vanhaecke
authors.affiliation: Department of Basic Medical Science - Histology Group, Ghent University, Belgium.
authors.forename: Maria
authors.initials: M
authors.lastname: Cornelissen
authors.affiliation: Polymer Chemistry and Biomaterials (PBM) Group, Department of Organic Chemistry, Ghent University, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Dubruel
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000166:cytology / Q000378:metabolism; D002113:Calcification, Physiologic; D002130:Calcium Phosphates / Q000737:chemistry*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D017616:Magnesium Compounds / Q000737:chemistry*; D008297:Male; D051379:Mice; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*; D010710:Phosphates / Q000737:chemistry*; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D000067996:RAW 264.7 Cells; D023822:Tissue Engineering
chemical_list: D002130:Calcium Phosphates; D020100:Hydrogels; D017616:Magnesium Compounds; D010710:Phosphates; D011135:Polysaccharides, Bacterial; C030781:magnesium phosphate; C048288:gellan gum; C020243:calcium phosphate
keywords: calcium phosphate; composite; cytocompatibility; enzyme; gellan gum; hydrogel; magnesium phosphate; osteoblast