Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
Acta Biomater. 2013 Jun;9(6):6898-904. doi: 10.1016/j.actbio.2013.02.018. Epub 2013 Feb 21.
A resorbable device for ligation of blood vessels was developed and tested in vitro to reveal the degradation profile of the device and to predict the clinical performance in terms of adequate mechanical support during a healing period of 1week. In addition, preliminary clinical testing was performed that showed complete hemostasis and good tissue grip of renal arteries in five pigs. The device was made by injection molding of poly(glycolide-co-trimethylene carbonate) triblock copolymer, and it consisted of a case with a locking mechanism connected to a partly perforated flexible band. A hydrolytic degradation study was carried out for 7, 30 and 60days in water and buffer medium, following the changes in mass, water absorption, pH and mechanical properties. A new rapid matrix-free laser desorption ionization-mass spectrometry (LDI-MS) method was developed for direct screening of degradation products released into the degradation medium. The combination of LDI-MS and electrospray ionization-mass spectrometry analyses enabled the comparison of the degradation product patterns in water and buffer medium. The identified degradation products were rich in trimethylene carbonate units, indicating preferential hydrolysis of amorphous regions where trimethylene units are located. The crystallinity of the material was doubled after 60days of hydrolysis, additionally confirming the preferential hydrolysis of trimethylene carbonate units and the enrichment of glycolide units in the remaining solid matrix. The mechanical performance of the perforated band was followed for the first week of hydrolysis and the results suggest that sufficient strength is retained during the healing time of the blood vessels.
我们开发并测试了一种可吸收的血管结扎装置,以揭示该装置的降解情况,并预测其在 1 周愈合期内的临床性能,即在适当的机械支撑下。此外,我们还进行了初步的临床测试,结果表明在五头猪的肾动脉中完全止血和良好的组织固定。该装置采用聚(乙交酯-共-三亚甲基碳酸酯)三嵌段共聚物注塑成型,由带有锁定机构的外壳和部分穿孔的柔性带组成。在水中和缓冲介质中进行了为期 7、30 和 60 天的水解降解研究,监测质量、吸水率、pH 值和机械性能的变化。我们开发了一种新的快速基质自由激光解吸电离-质谱(LDI-MS)方法,用于直接筛选降解产物释放到降解介质中。LDI-MS 和电喷雾电离-质谱分析的结合使我们能够比较水和缓冲介质中降解产物的模式。鉴定的降解产物富含三亚甲基碳酸酯单元,表明无定形区域(三亚甲基单元所在的区域)优先水解。水解 60 天后,材料的结晶度增加了一倍,这进一步证实了三亚甲基碳酸酯单元的优先水解以及剩余固体基质中乙交酯单元的富集。我们还跟踪了穿孔带在水解的第一周的机械性能,结果表明,在血管愈合期间保留了足够的强度。