异种生物瓣膜生物材料鞣制的研究

A research into the tanning of biological materials for heterogenic biovalves

目的 :评价复合鞣制的生物材料性能及异种生物瓣膜临床应用效果。方法 :用戊二醛、阳离子油、三氧化二铬及甘油等复合鞣制的生物材料 ,用光镜和电镜做组织形态学及超微结构观察 ;用万能实验机做力学性能测试 ;用傅立叶红外光谱测试仪测定羧基含量 ;人工心脏瓣膜疲劳寿命实验台加速测试。结果 :光镜下仍可见到浆膜层的间皮细胞大部分存在 ,间皮细胞下层由致密的胶原纤维组成 ;投射电镜下可见胶原纤维排列整齐、致密 ,细胞结构完整 ,铬离子能均匀地浸入细胞内 ;扫描电镜下可见到经阳离子油预处理的生物材料铬化后胶原纤维致密 ,排列整齐 ,呈网状分布 ,而未经阳离子油预处理的则胶原纤维粗大、排列无序 ;力学性能测试 :牛心包厚度 0 4 4± 0 13mm ,收缩温度在 86～ 90℃时材料最柔软 ,抗张强度 19 9～ 2 5 9N mm2 ,延伸率 4 3 4 %～ 4 6 0 % ;傅立叶红外光谱图 174 1 11cm- 1 处羧基 (CO OH- 1 )峰明显降低 ,表明羧基含量减少 ,且酰胺峰位左移 ,表明牛心包膜结构紧密 ;人工心脏瓣膜加速疲劳实验测试 ,猪主动脉瓣膜经受了 3 892亿次循环 ,牛心包瓣膜经受了 3 888亿次循环 ,从受力疲劳方面看将能经受住大约 10年的寿命。结论 :用戊二醛预处理再经阳离子油、三氧化二铬、甘油等复合鞣制生物材料 。

Objective:To evaluate the capacity of biological materials tanned with a compound method and the clinical performance of biovalves made of them.Method:The biological materials were compoundly tanned with amylic aldehyde,cation fat,chromium trioxide and glycerol.We exzamined the histological morphology and ultra structure of the biological materials with photologic and electron microscope.We tested the mechanic performance of these materials with the almighty experimental instrument.We measured the content of hydroxyls in the materials with the Fourier infrared spectrun detector.The longevity of the prosthetic biological cardiac valves made of the materials with an accelerated wearing experiment in laboratory.Result:Most of the mesothelial cells of the biological materials existed in the tumica serosa in the photologic microscopical field.The inferior layer was formed by pyknomorphic collagenous fibers.Under the projective electron microscope,the collagenous fibers were dense and lined up in order.The cellular structure was whole.Under the scanning electron microscope,the collagenous fibers of the biological materials pre\|treated with the cation fat were dense and lined up in order after chromatinationand were distributed in reticulation.In the control materials,the collagenous fibers were rough ahd bulky and lined up out of order.The mechanic tests showed that the thickness of the bovine pericardium was 0.44±0.13 mm.The materials were softest at the contracting temperature of 86℃ to 90℃.The tensile strength of the materials was 19.9 to 25.9 N/mm\+2 and the extension rate was 43.4% to 46%.The peak of the hydroxyls decreased significantly at the wave length of 1741.11 cm -1 in the Fourier infrared spectrum,which meaned that the content of the hydroxyls reduced.The peak of the amides shifted to the left,which meaned that structure of the bovine pericardium was compact.The swine aortic valve experienced 3.892×10 8 cycles in the accelerated wearing tests,and the bovine pericardial valve,3.888×10\+8 cycles.Estimated from the tests,the biovalves will endure for about ten years.Conclusion:The method to pre\|treat the biological materials with amylic aldehyde and then compoundly tan them with cation fat,chromium trioxide and glycerol can increase firnness and softness of the materials and prevent calcification of the biovalves and then delay the degeneration. [