title: Rapid screening of mineralization capacity of biomaterials by means of quantification of enzymatically deposited calcium phosphate.
abstract: The current study focused on the development of a rapid, straightforward quantification method based on the use of enzymatic decomposition of urea using urease to assess the mineralization capacity of a wide range of biomaterials for bone regeneration. Urea-containing mineralizing solutions (MSs) (containing: Na2HPO4, CaCl2, and NaCl at 37°C and pH 6.0) were used in the mineralization experiments. Urease was added to these solutions to induce enzymatic decomposition of urea resulting in increased pH and deposition of calcium phosphate. By optimizing the ionic and urease concentrations in these MSs, it was shown that the proposed system could mineralize titanium substrates with six different pretreatments, as opposed to normal simulated body fluid that mineralized only two of them. It was possible to rank the mineralization capacity of these substrates by measuring the amount of calcium deposited. Furthermore, the ranking of (i) various polymeric substrates and (ii) hydrogels with and without functionalization with calcium-binding bisphosphonate groups was also possible. These results confirm that the proposed testing system has a broad applicability in the field of biomaterials due to its inherent versatility and discriminative power.
authors.affiliation: 1 Department of Biomaterials, Radboud University Medical Centre , Nijmegen, The Netherlands .
authors.forename: Arnold W G
authors.initials: AW
authors.lastname: Nijhuis
authors.forename: Shinji
authors.initials: S
authors.lastname: Takemoto
authors.forename: M Reza
authors.initials: MR
authors.lastname: Nejadnik
authors.forename: Yubao
authors.initials: Y
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Yang
authors.forename: Dmitri A
authors.initials: DA
authors.lastname: Ossipov
authors.forename: Jons
authors.initials: J
authors.lastname: Hilborn
authors.forename: Antonios G
authors.initials: AG
authors.lastname: Mikos
authors.forename: Masao
authors.initials: M
authors.lastname: Yoshinari
authors.forename: John A
authors.initials: JA
authors.lastname: Jansen
authors.forename: Sander C G
authors.initials: SC
authors.lastname: Leeuwenburgh
mesh_terms: D001672:Biocompatible Materials / Q000494:pharmacology*; D002113:Calcification, Physiologic / Q000187:drug effects*; D002118:Calcium / Q000032:analysis; D002130:Calcium Phosphates / Q000032:analysis / Q000378:metabolism*; D007477:Ions; D008855:Microscopy, Electron, Scanning; D056951:Photoelectron Spectroscopy; D011091:Polyesters / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014025:Titanium / Q000494:pharmacology; D014510:Urease / Q000378:metabolism*
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; D007477:Ions; D011091:Polyesters; C469550:oligo(poly(ethylene glycol)fumarate); D011092:Polyethylene Glycols; C020243:calcium phosphate; D014025:Titanium; D014510:Urease; D002118:Calcium