壳聚糖微球复合丝素基硫酸钙骨水泥的理化特性

背景：脊柱成形和脊柱后凸成形治疗中采用的硫酸钙骨水泥理化性质好，对人体无毒性作用，同时具有降解性能，但单独使用降解较快。目的：研制具有载药缓释功能的壳聚糖微球丝素基硫酸钙骨水泥。方法：采用三聚磷酸钠乳化交联法制备壳聚糖微球。采用浓度分别为3%，6%，9%的丝素溶液与CaSO4？0.5H 2 O混合，通过万能力学试验机确定骨水泥力学性能最佳时的丝素浓度，在此浓度下，按壳聚糖微球占CaSO 4？0.5H 2 O的质量比分别为0.5%，1%，5%的比例制备壳聚糖微球丝素基硫酸钙骨水泥，测定其抗压强度，并通过X射线多晶衍射仪及傅里叶红外光谱明确达到最佳抗压强度组的骨水泥成分，电镜观察复合骨水泥中壳聚糖微球的形态。结果与结论：当丝素溶液浓度为6%，壳聚糖微球含量为0.5%时，复合骨水泥的抗压强度最大，为（39.17＆#177;1.96） MPa，此时复合骨水泥的初凝时间为（12.99＆#177;1.63） min，终凝时间为（21.55＆#177;0.54） min；骨水泥中主要晶相组成为硫酸钙，傅里叶红外光谱结果证实复合骨水泥中含有丝素及壳聚糖；复合骨水泥中的微球表面稍有皱缩，但球形仍然完整，未见明显破坏，可见在制备复合骨水泥的过程中微球能保持稳定而不被破坏。

Physicochemical properties of chitosan microspheres/silk fibroin/calcium sulfate bone cement

BACKGROUND：Calcium sulfate used in kyphoplasty and vertebrolplasty has good physical and chemical properties, exerts no toxic effects on human body and has the degradation performance. But its main drawback is rapid degradation. OBJECTIVE：To develop a chitosan microsphere with silk fibroin/calcium sulfate cement to prepare drug carrier system. METHODS：Chitosan microspheres were prepared by the emulsion method. Scanning electron microscopy, particle size analysis and swel ing rate were used to study the properties of the microspheres. Different silk concentrations （3%, 6%and 9%） and weight rates （0.5%,1%and 5%） of chitosan microspheres were used to determine the best formula which has the strongest mechanical properties. The composition of this composite bone cement was detected by using X-ray diffraction and Fourier transform infrared spectroscopy. RESULTS AND CONCLUSION：When the concentration of silk fibroin was 6%and weight rate of chitosan microspheres was 0.5%, we could obtain the maximum compressive strength, which was （39.17＆#177;1.96） MPa. With this composition, the initial setting time was （12.99＆#177;1.63） minutes and the final setting time was （21.55＆#177;0.54） minutes. The results from X-ray diffraction and Fourier transform infrared spectroscopy demonstrated that the main phase composition was calcium sulfate, and silk and chitosan were also included. The composite chitosan microspheres exhibited a slightly wrinkled surface, but were stil intact in spherical shape, indicating the＆amp;nbsp;preparation of chitosan microspheres/silk fibroin/calcium sulfate cement was reliable and the product had good structures and properties.