Nijhuis Arnold W G, Takemoto Shinji, Nejadnik M Reza, Li Yubao, Yang Xia, Ossipov Dmitri A, Hilborn Jons, Mikos Antonios G, Yoshinari Masao, Jansen John A, Leeuwenburgh Sander C G
1 Department of Biomaterials, Radboud University Medical Centre , Nijmegen, The Netherlands .
Tissue Eng Part C Methods. 2014 Oct;20(10):838-50. doi: 10.1089/ten.TEC.2013.0334. Epub 2014 May 1.
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.
当前的研究聚焦于开发一种基于利用脲酶对尿素进行酶解的快速、直接的定量方法，以评估多种用于骨再生的生物材料的矿化能力。矿化实验中使用了含尿素的矿化溶液（MSs）（含有：37°C、pH 6.0条件下的Na2HPO4、CaCl2和NaCl）。向这些溶液中添加脲酶以诱导尿素的酶解，从而导致pH升高和磷酸钙沉积。通过优化这些MSs中的离子浓度和脲酶浓度，结果表明，与仅能矿化其中两种的正常模拟体液相反，所提出的系统能够使经过六种不同预处理的钛基底矿化。通过测量钙沉积量，可以对这些基底的矿化能力进行排序。此外，对（i）各种聚合物基底以及（ii）具有和不具有钙结合双膦酸酯基团功能化的水凝胶进行排序也是可行的。这些结果证实，所提出的测试系统因其固有的通用性和区分能力，在生物材料领域具有广泛的适用性。
