Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.
J Biomed Mater Res A. 2014 Apr;102(4):982-90. doi: 10.1002/jbm.a.34759. Epub 2013 May 30.
Biodegradable stents can alleviate intestinal obstruction and stenosis in patients. The objective of this study was to develop a biodegradable polydioxanone (PDO) stent using weft-knitting technology and then investigate its biodegradation behaviors in vitro. PDO monofilament with linear density of 100 ± 10 tex was knitted into a tubular stent using a tubular weft-knitting machine. The physical and mechanical properties were evaluated according to the British standard BS EN 13895:2003 and ISO 7198:1998. The biodegradation behaviors of PDO weft-knitted stent in a phosphate buffer solution (pH = 6.8 ± 0.2, 37 ± 0.5 °C) were then investigated. The results showed that the stent maintained more than 60% of its original radial force above 12 weeks. During the 16 weeks of degradation, weight, crystallization, and pH change indicated the degradation medium was diffused into the chain segments of low molecular weight due to the rupture of ester bonds in the monofilament. Fourier transform infrared spectroscopy results demonstrated that the chemical structure of PDO polymer is stable during the in vitro degradation. In conclusion, this biodegradable stent can find valuable applications in treatment of intestinal obstruction and stenosis clinically.
可生物降解支架可缓解患者的肠梗阻和狭窄。本研究旨在采用经编技术开发一种可生物降解的聚对二氧环己酮（PDO）支架，并研究其体外的生物降解性能。采用管状经编机，将线密度为 100±10tex 的 PDO 单丝编织成管状支架。根据英国标准 BS EN 13895：2003 和 ISO 7198：1998 评估其物理和机械性能。然后，在磷酸盐缓冲溶液（pH=6.8±0.2，37±0.5℃）中研究了 PDO 经编织支架的生物降解性能。结果表明，在 12 周以上的时间内，支架保持了超过 60%的原始径向力。在 16 周的降解过程中，重量、结晶度和 pH 值的变化表明，由于单丝中酯键的断裂，降解介质扩散到低分子量的链段中。傅里叶变换红外光谱结果表明，PDO 聚合物的化学结构在体外降解过程中保持稳定。总之，这种可生物降解的支架在临床上治疗肠梗阻和狭窄方面具有很大的应用价值。
