放射性覆膜金属支架制备方法的研究

Preparation of ^(32)P radioactive covered metal stent:an experimental study in vitro

目的探索32P放射性覆膜金属支架的制备方法。方法通过比较聚乙烯醇和聚氨酯以及不同制备工艺制作的放射性膜材料在生理盐水中的32P放射性物质的泄漏率;测量不同聚氨酯涂膜工艺和同一膜不同部分的质量和放射性计数率,测量每部分单位质量的放射性计数率,评价支架膜上放射性物质的均匀性;比较旋转滴涂法和浸涂法在支架上涂膜的不同效果。结果聚乙烯醇中放射性物质在生理盐水中泄漏率达90%,聚氨酯能有效降低放射性物质在生理盐水中的泄漏,在其表面再涂聚氨酯涂层,泄漏率处于本底水平;不同聚氨酯膜中的放射性物质分布百分差率差异没有统计学意义(非参数检验Mann-Whitney test方法,U=10.0,P=0.602>0.05),同一膜材料中放射性物质分布平均百分差率为11.76%;旋转滴涂法在支架上形成的膜层不均匀,出现穿孔现象,而浸涂法可形成均匀的膜层。结论以聚氨酯作为覆膜材料,能有效减低32P放射性物质的泄漏,同时放射性物质在膜材料中的分布亦较均匀。

Objective To optimize the preparation technique of 32P radioactive covered metal stent.Methods The 32P radioactive material leakage rate in saline of polyvinyl alcohol membrane and polyurethane membrane was calculated respectively.The 32P radioactive material disposition homogeneity in different polyurethane membranes and in different portions of polyurethane membrane was determined separately.Polyurethane membrane homogeneity by drop-coating and dip-coating on metal stent was evaluated respectively.The results were statistically analyzed.Results The 32P radioactive material leakage rate in saline of polyvinyl alcohol membrane was 90%,but the 32P radioactive material leakage rate of polyurethane membrane was very low.No significant difference in the 32P radioactive disposition homogeneity existed between different polyurethane membranes（Mann-Whitney Test,U = 10.0,P = 0.602 0.05）,and the mean difference in different portion of polyurethane membrane was 11.76%.The polyurethane membrane on stent covered by dip-coating technique was homogeneous,but the membrane was not homogeneous,even with perforation,if covered by drop-coating technique.Conclusion The polyurethane membrane on metallic stent which is covered by dip-coating technique can decrease the 32P radioactive material leakage in saline,and the distribution of the radioactive material in such a membrane is quite homogeneous.