胶原/磷酸钙生物矿化的紫外吸收动力学研究

用紫外分光光度法研究了胶原生物矿化的机理。通过对反应液做定时波长扫描 ,获得一组包含重要过程信息的光谱曲线和动力学曲线。首次发现阶梯形的动力学曲线上出现一个波谷 ,磷酸钙 (磷酸氢钙 )初始浓度增大时 ,波谷增大 ,位置提前。结合波谷前后样品的X射线衍射谱分析 ,指出 :胶原生物矿化过程中 ,相继发生凝胶化和相分离。载钙胶原分子通过新生成的磷酸氢钙进行“点对点”交联 ,在交联网格中磷酸氢钙发生相分离 ,从而产生波谷现象。用该机理解释了胶原矿化中各种紫外吸收的光谱现象。

Kinetic Study on Collagen Mineralization by Ultraviolet Absorption Spectra

The mechanism of collagen mineralization was studied by ultraviolet photometry method. The reaction solution was determined using ultraviolet-visible spectrophotometer by the method of repeat scanning wavelength. The recorded curves provided the spectroscopic and kinetics information of the reaction solution. It was found that the wave trough appeared on the step-like kinetic curve of mineralization of collagen. With the increase in initial concentration of calcium phosphate, the wave trough intensity increased and its position moved forward. The curves of scanning wavelength at different time showed different patterns. By analyzing the change in scanning wavelength curves, and the X-ray diffraction spectra of specimens before and after the wave trough position (the specimens were obtained by quickly freezing the solution and freeze-drying), it was suggested that gelation and phase separation occurred during the process of collagen mineralization. Collagen molecules loading calcium were cross-linked by newly formed DCPD in a "point to point" mode. The phase separation occurred in the fluid-filled space and the wave trough occurred in the ultraviolet absorption spectrum. Based on the mechanism the varieties of phenomena in the ultraviolet absorption spectrum during collagen mineralization were explained.