Biomedical applications of polyurethanes: A review of past promises, present realities, and a vibrant future
Biomedical applications of polyurethanes: A review of past promises, present realities, and a vibrant future
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DOI：
10.1177/088532829901400104
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发表时间：
1999-07-01
影响因子：
2.9
通讯作者：
Zdrahala, IJ
中科院分区：
文献类型：
--
作者：
Zdrahala, RJ;Zdrahala, IJ
聚氨酯具有广泛的结构/性能多样性，是当今已知的生物和血液相容性最强的材料之一。这些材料在从导管到全人工心脏等许多医疗设备的开发中发挥了重要作用。耐久性、弹性、弹性体特性、抗疲劳性、顺应性以及愈合过程中身体的接受度或耐受性等特性通常与聚氨酯联系在一起。此外，通过亲水/疏水平衡或通过连接生物活性物质（例如抗凝剂或生物可识别基团）进行本体和表面改性的倾向可以通过聚氨酯结构的典型化学基团实现。这些修改旨在调节和增强设备或植入物的接受度和愈合。许多创新的加工技术被用来制造功能装置，其感觉和行为通常类似于天然组织。水解不稳定的聚酯聚氨酯被更耐腐蚀但氧化敏感的基于聚醚多元醇的聚氨酯及其含有有机硅和其他改性聚合物中间体的克隆所取代。然而，在长期植入过程中观察到的慢性体内不稳定性成为许多应用的主要障碍。目前，使用更抗氧化的聚碳酸酯多元醇作为软链段，与维生素E等抗氧化剂结合，提供了可以在体内持续数年的材料。这些应用涵盖心血管设备、人造器官、组织替代和增强、性能增强涂层等。原位聚合、交联系统可以进一步扩展这种生物耐久性。未来将通过重新审视化学控制生物降解，结合迷你版 RIM 技术和微创外科手术，通过将反应材料输送到体内的特定部位并在原位聚合物质，在体内形成支架，从而扩大这一领域。该支架将通过细胞附着、增殖、炎症控制和愈合为组织再生提供锚点。
Polyurethanes, having extensive structure/property diversity, are one of the most bio- and blood-compatible materials known today. These materials played a major role in the development of many medical devices ranging from catheters to total artificial heart. Properties such as durability, elasticity, elastomer-like character, fatigue resistance, compliance, and acceptance or tolerance in the body during the healing, became often associated with polyurethanes. Furthermore, propensity for bulk and surface modification via hydrophilic/hydrophobic balance or by attachments of biologically active species such as anticoagulants or biorecognizable groups are possible via chemical groups typical for polyurethane structure. These modifications are designed to mediate and enhance the acceptance and healing of the device or implant. Many innovative processing technologies are used to fabricate functional devices, feeling and often behaving like natural tissue.The hydrolytically unstable polyester polyurethanes were replaced by more resistant but oxidation-sensitive polyether polyols based polyurethanes and their clones containing silicone and other modifying polymeric intermediates. Chronic in vivo instability, however, observed on prolonged implantation, became a major roadblock for many applications.Presently, utilization of more oxidation resistant polycarbonate polyols as soft segments, in combination with antioxidants such as Vitamin E, offer materials which can endure in the body for several years. The applications cover cardiovascular devices, artificial organs, tissue replacement and augmentation, performance enhancing coatings and many others. In situ polymerized, cross-linked systems could extend this biodurability even further.The future will expand this field by revisiting chemically-controlled biodegradation, in combination with a mini-version of RIM technology and minimally invasive surgical procedures, to form, in vivo, a scaffold, by delivery of reacting materials to the specific site in the body and polymerizing the mass in situ. This scaffold will provide anchor for tissue regeneration via cell attachment, proliferation, control of inflammation, and healing.