Shape memory polymer foams for cerebral aneurysm reparation: Effects of plasma sterilization on physical properties and cytocompatibility
Shape memory polymer foams for cerebral aneurysm reparation: Effects of plasma sterilization on physical properties and cytocompatibility
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DOI：
10.1016/j.actbio.2008.11.017
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发表时间：
2009-06-01
影响因子：
9.7
通讯作者：
Fare, Silvia
中科院分区：
文献类型：
--
作者：
De Nardo, Luigi;Alberti, Rachele;Fare, Silvia
形状记忆聚氨酯（SMPU）是动脉瘤栓塞的有前途的候选材料，因为它们可以克服与这些临床手术相关的临床问题。在这项工作中，我们报告的表征的物理化学，热机械和体外界面性能的两个SMPU泡沫（冷休眠弹性记忆，CHEM），提出作为材料的栓塞装置在微创手术。此外，由于器械灭菌对于体内应用是强制性的，因此还评价了等离子体灭菌后对泡沫性能的影响。两种泡沫（CHEM 3520和CHEM 5520）在恒定加热速率下进行的常规形状恢复测试中显示出优异的形状恢复能力（恢复率，R-r，高达99%）。通过动态力学分析（DMA）中的tan δ峰测定的转变温度（T-transs）对于CHEM 3520和5520分别为32.2和45.1 ℃。在37 ℃下的恢复试验中，T-反式值影响形状记忆能力，该试验模拟了器械植入后的行为：事实上，T-反式较低的泡沫的R-r显著更高（CHEM 3520和CHEM 5520的R-r分别约为82%和46%）。在通过Sterrad（R）灭菌系统进行等离子体灭菌后，观察到开放孔隙率增加：这可能是由于灭菌循环;然而，未观察到对形状恢复行为的影响。此外，在体外细胞毒性试验中，对与泡沫接触长达7天的细胞培养基浸提液进行等离子体处理对L929细胞无显著影响。此外，直接细胞相容性测试显示L929细胞在CHEM泡沫上的良好定殖和生长，表明体内愈合过程的有效性。所有这些结果似乎表明，CHEM泡沫可有利地用于制造用于动脉瘤微创栓塞手术的器械。(c)2008 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
Shape memory polyurethanes (SMPUs) represent promising candidate materials for aneurysm embolization, since they could enable clinical problems still associated with these clinical procedures to be overcome. In this work, we report on the characterization of physicochemical, thermomechanical and in vitro interface properties of two SMPU foams (Cold Hibernated Elastic Memory, CHEM), proposed as a material for embolization devices in minimally invasive procedures. Moreover, because device sterilization is mandatory for in vivo applications, effects on the properties of the foams after plasma sterilization were also evaluated. Both foams (CHEM 3520 and CHEM 5520) showed excellent shape recovery ability (recovery rate, R-r, up to 99%) in conventional shape recovery tests, performed at constant heating rate. Transition temperatures (T-trans), determined by tan 6 peaks in dynamic mechanical analysis (DMA), were 32.2 and 45.1 degrees C, for CHEM 3520 and 5520, respectively. The value of T-trans affects shape memory ability in the recovery test at 37 degrees C, which simulates the behavior after implantation of the device: in fact, R-r was significantly higher for lower T-trans foam (R-r approximate to 82% and R-r approximate to 46%, respectively, for CHEM 3520 and CHEM 5520). After plasma sterilization performed by a Sterrad (R) sterilization system, an increase in open porosity was observed: this is probably due to the sterilization cycle; however, no effects on shape recovery behavior were observed. Furthermore, plasma treatment had no significant effect on L929 cells in in vitro cytotoxicity tests, performed on cell culture medium extracts in contact with foams for up to 7 days. Moreover, direct cytocompatibility tests showed a good colonization and growth from L929 cells on CHEM foams, suggesting the effectiveness of an in vivo healing process. All these results seem to suggest that CHEM foams could be advantageously used for manufacturing devices for mini-invasive embolization procedures of aneurysms. (c) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.