一种新型可降解输尿管支架管的体外力学性能研究

Mechanical properties study of a novel degradable ureteral stent in vitro

目的设计一种复合结构的可降解输尿管支架管,通过体外评估其力学性能进而探讨该支架管潜在的临床应用价值。方法制作可降解输尿管支架管,并比较其添加涂层前后的力学性能差异,同时在体外观察支架管在人尿液及pH值分别为5.8及7.4的PBS缓冲液降解过程中的力学性能变化。结果成功制作出两种分别用于成年人及儿童的新型可降解支架管,添加涂层和未添加涂层的支架管的停止强力及拉伸强度差异有统计学意义(P<0.05)。添加涂层和未添加涂层的5.8F及4.5F支架管停止强力(cN)分别是409.40±8.62 vs 362.60±10.69和390.60±9.13 vs 366.20±5.20,同时拉伸强度(MPa)分别为81.69±6.13 vs 79.99±5.04和121.80±5.26 vs 113.94±4.50。新型可降解输尿管支架管在3种不同液体中降解2周后仍具有较好的力学性能。结论新型可降解输尿管支架管具有良好的力学性能,有潜在的临床应用价值。

Objective A novel degradable ureteral stent which had a special composite structure was designed.Its mechanical properties were evaluated in vitro to explore its potential clinical promise.Methods The ureteral stent with a new coating was fabricated and its mechanical properties were evaluated.The degradable ureteral stent was evaluated in vitro with three kinds of degradable medium:human urine and phosphate buffer solutions(pH=5.8 and 7.4)so as to compare the effect of mechanical properties.Results Two different stents were prepared that can be used for adults or children.The difference in radical compression and tensile strength of coated and uncoated stent was statistically significant(P<0.05).The radical compression and tensile strength of the coated and uncoated 5.8F and 4.5F stent was 409.40±8.62 vs 362.60±10.69 and 390.60±9.13 vs 366.20±5.20 while the tensile strength(MPa)was 81.69±6.13 vs 79.99±5.04 and 121.80±5.26 vs 113.94±4.50.There were still good mechanical properties until the end of the second week in 3 kinds of media.Conclusion The novel degradable ureteral stent has good mechanical properties.It shows potential clinical promise.