title: Cytocompatibility evaluation of microwave sintered biphasic calcium phosphate scaffolds synthesized using pH control.
abstract: Compounds belonging to the calcium phosphate (CaP) system are known to be major constituents of bone and are bioactive to different extents in vitro and in vivo. Their chemical similarity makes them prime candidates for implants and bone tissue engineering scaffolds. CaP nanoparticles of amorphous hydroxyapatite (aHA) and dicalcium phosphate dihydrate (DCPD) were synthesized using chemical precipitation. Uniaxially pressed aHA and DCPD powders were subjected to microwave radiation to promote solid state phase transformations resulting in crystalline hydroxyapatite (HA), tricalcium phosphate (TCP) and biphasic compositions: HA/TCP and TCP/calcium pyrophosphate (CPP) and their subsequent densification. Phase composition of microwave sintered compacts was confirmed via X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Solution pH during crystal growth was found to have a profound effect on particle morphology and post-sintered phases, despite constant sintering temperature. Cytocompatibility assessment using 7F2 cells, corresponding to adult mouse osteoblasts, on microwave and conventional, furnace sintered samples demonstrated that manufacturing method does not impact cellular viability after 24 h or proliferation over 7 days. New CaP deposition and extracellular matrix components were observed in vitro via scanning electron microscopy (SEM).
authors.affiliation: Department of Biomedical Engineering, Colleges of Engineering and Medicine, University of Toledo, 2801W. Bancroft Street, 5051 Nitschke Hall MS 303, Toledo, OH 43606, USA. darcy.wagner@rockets.utoledo.edu
authors.forename: Darcy E
authors.initials: DE
authors.lastname: Wagner
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Jones
authors.forename: Huan
authors.initials: H
authors.lastname: Zhou
authors.forename: Sarit B
authors.initials: SB
authors.lastname: Bhaduri
mesh_terms: D000818:Animals; D002130:Calcium Phosphates / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D051379:Mice; D008872:Microwaves; D053758:Nanoparticles / Q000648:ultrastructure; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects; D011208:Powders; D017550:Spectroscopy, Fourier Transform Infrared; D054457:Tissue Scaffolds / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D002130:Calcium Phosphates; D011208:Powders; C494366:calcium phosphate, dibasic, dihydrate
keywords: Biphasic calcium phosphates; Calcium pyrophosphate; Hydroxyapatite; Microwave sintering; Tissue engineering; Tricalcium phosphate