Development of biocompatible metal-BMP composit

为了制备水溶性BMP，进行S-200凝胶过滤，然后截留分子量大于40，000 Da的BMP。将10，000 - 30，000 Da的级分用水透析并离心出ppt。将上清液冻干。将该BMP与粉末状纯金属（Ag、Al、Au、Co、Cr、Cu、Fe、Ge、In、Ir、Mn、Mo、Ni、Pb、Pd、Pt、Sb、Sn、Ta、Ti、W、Zn）复合，研究各金属对新骨形成的影响。在植入Au、Mo、Ti时，这些金属的存在对新骨形成没有抑制作用。而Cu、Fe、Sb则明显抑制成骨诱导作用，新骨形成不完全。对于其他金属，观察到新骨形成，但新骨的量减少。测定[~ 3 H]-胸腺嘧啶核苷、[~ 35]-硫酸盐的摄取量，定量分析金、铂、镍、钛对软骨细胞的毒性和软骨形成的影响。金、Au、钛对软骨细胞的DNA合成无明显抑制作用，镍对软骨细胞的DNA合成有明显抑制作用。在GAG合成中获得了相同的现象。在某些条件下，铂对骨活性有轻微的抑制作用，而在通常的实验条件下，铂对新骨形成无影响。因此，金铂合金似乎是一个很好的候选人开发的生物相容性合金。在Au-Pt中添加Mo将是一种很好的改性。Ti显示出如前所述的生物相容性金属的优异性能。

In order to prepare water soluble BMP,S-200 gel filtration was performed, then higher molecular weight than 40,000 Da was cut off. The fraction of 10,000-30,000 Da was dialyzed against water and centrifuge out the ppt. The supernatant was lyophilized. This was water soluble BMP.This BMP and powdered pure metals(Ag,Al,Au,Co,Cr,Cu,Fe,Ge,In,Ir,Mn,Mo,Ni,Pb,Pd,Pt,Sb,Sn,Ta,Ti,W,Zn)were combined, then the effect of each metals on new bone formation was investigated. In the implantation of Au,Mo,Ti, there were no inhibition of new bone formation under the existence of these metals. On the contrary, Cu,Fe,Sb suppressed osteoinduction remarkably and new bone formation did not occur completely. With other metals, new bone formation were observed but the amounts of new bone were decreased. Uptake of [3H]-thyamidine, [35]-sulfate were measured to know the DNA synthesis, GAG (glycosaminoglycan) for the quantitative analysis of cytotoxity and chondrogenesis by Au,Pt,Ni,Ti.Au,Pt.Ti did not suppress the DNA synthesis, and Ni did remarkably. Same phenomena was obtained in GAG synthesis. In some condition Pt inhibit osteoactivity slightyl, however in usual experimental condition, it did not effect on new bone formation. Consequently, Au-Pt alloy seems to be a excellent candidate for the developing biocompatible alloy. Addition of Mo to Au-Pt will be a good modification. Ti showed excellent property for a biocompatible metal mentioned as previously.