In vitro evaluation of biocompatibility of Ti–Mo–Sn–Zr superelastic alloy

Abstract

Shape memory alloys (SMAs) including superelastic alloys have unique properties such as shape memory and superelasticity, thus they are recognized as very useful biomaterials. These properties are very advantageous for medical use, and actually the SMA wires have been widely used in medical field. However, biocompatibility of nickel-titanium (Ni-Ti) alloy, which is the only practical SMA at present, has been questioned because of its high nickel content. The aim of this study was to evaluate the biocompatibility of a newly developed Ni-free Ti-based SMA for medical use. The newly developed SMA made of Ti-Mo-Sn-Zr system was processed into a disk of 15.1 mm in diameter. Pure titanium of the same shape was prepared as control. All the disk surfaces were polished using emery papers, #120, #400, and #600. Scanning electron microscopy and a 3D optics profiler were used to evaluate the surface of the materials. In vitro evaluations included colony examination for evaluation of the cell cytotoxicity, DNA quantification for the cell proliferation, Alamar blue assay for metabolic activity, FDA staining for the live cell imaging, and cell cycle analysis, using Chinese hamster fibroblastic V-79 cells and mouse osteoblastic MC3T3-E1 cells. In colony examination and DNA quantification, there was no significant difference between the Ti-Mo-Sn-Zr and the pure titanium. In FDA staining, cultured cells on the Ti-Mo-Sn-Zr alloy showed the same biocompatibility as those on the pure titanium. The present results suggest that the newly developed Ti-Mo-Sn-Zr alloy showed the high biocompatibility comparable to pure titanium and can be used as efficient biomaterial for medical use.

SP600125 Enhances Temperature-Controlled Repeated Thermal Stimulation-Induced Neurite Outgrowth in PC12-P1F1 Cells

“…For live cell imaging, fluorescein diacetate staining assay was performed as described previously [ 40 ]. The cells were incubated at 37 °C in an atmosphere of 5% CO 2 and examined on days 0 and 7 during the above-described neuritogenesis assay.…”

Phase Constitution and Mechanical Properties of Ti‐Mo‐Sn‐Zr Shape Memory Alloys

“…Then, we have focused on Zr addition to TiMo-Sn alloy as a quaternary additional element in order to solve these problems. In our previous research, it was reported that the biocompatibility of a Ti-3Mo-6Sn-5.2Zr alloy is comparable to the pure Ti [15]. In addition, it was also reported that Zr addition to Ti-Mo-Sn alloy decreases the martensitic transformation temperature by 42 K / mol%Zr with small change of the lattice deformation strain [16].…”

Effect of Zr Addition on Mechanical and Shape Memory Properties of Ti-5Mo-3Sn Alloys

“…，Ti Ta 基 3 6) ，Ti Mo 基 7 10) 形状 記憶合金といった多くの合金が研究されている．しかし， 17) ．さらに，Ti 3Mo 6Sn 5Zr(mol)合金では，時効温 度 に よ り 析 出 a 相 の 形 状 が 変 化 す る こ と も 報 告 し て い…”