Surface Engineering of Chemically Inert Polymers for Medical and Biomedical Applications

由于医用纺织品和热塑性聚合物的表面与微生物、细胞和生物系统接触，表面性质起着重要的作用。对现有的纺织品和聚合物材料进行表面工程是开发新材料以满足医学应用和防护的严格要求的一种经济方法。例如，大多数医院隐私窗帘在使用的第一周就被污染了。随后，医护人员在洗手后触摸窗帘，然后触摸患者。窗帘成为医院交叉感染的媒介。隐私窗帘表面的耐用抗菌功能有助于降低医院交叉感染的可能性。**这项研究的最终目标是开发新的方法，在对物理性能影响最小的情况下，对生物医学和医疗应用的化学惰性聚合物材料进行持久而有效的表面改性。在之前的NSERC发现计划中，我们的研究小组成功地开发了一种新的非破坏性和有效的表面改性技术，用于聚对苯二甲酸乙二酯(PET)等化学惰性热塑性聚合物：通过形成功能聚合物和基材聚合物的互穿网络(IPN)进行表面改性。这种表面改性是耐用的，除非基材聚合物被溶解或熔化。这种新型的表面改性技术简单易用，用途广泛(适用于许多热塑性聚合物)，保持了改性聚合物基材的机械强度，并可以获得高密度的表面官能团。虽然改性涤纶织物的拉伸强度得到了很好的保持，但改性基材的柔韧性受到了一定程度的影响。为了优化表面修饰，最大限度地减少对聚合物基质弹性的负面影响，这对某些医疗应用是必不可少的，如血管移植和伤口护理敷料，我们建议进行基础研究，以三维方式表征互穿网络，加深对过程-结构-性能关系的了解，并以最小的交联量将功能聚合物(如抗菌聚合物)持久地互锁到热塑性聚合物上。此外，我们会研究策略，在医用纺织品和植入物上达到更有效和选择性的抗菌活性，使医用纺织品上的细菌得以快速灭活，并以最低限度的人体细胞毒性有效和选择性地杀灭植入物上的细菌。**我们预计，拟议的研究将在用于医疗纺织品、生物材料和医疗器械的化学惰性热塑性聚合物的表面改性科学方面取得突破。这项工作的成果可以作为生物材料科学家设计下一代生物材料的工具，这些材料可以更好地应对组织/血液材料界面的生物挑战，并为制造个人防护装备、生物材料和医疗器械的行业提供技术支持。获得更有效的抗菌表面策略的研究将为制备高效和选择性的杀菌PET和聚氨酯奠定基础，这些材料用于隐私窗帘、护士制服和手术窗帘，以减少交叉感染，并用于内窥镜和生物被膜控制的导管。拟议的工作将导致在聚合物化学、分析化学、医用纺织品和生物材料科学方面培养具有跨学科技能的高素质人才。

Since the surface of medical use textiles and thermoplastic polymers is in contact with microorganisms, cells and biological systems, surface properties play an important role. Surface engineering of existing textiles and polymeric materials is an economical way to develop new materials to meet the rigorous requirements for medical applications and protection. For example, the majority of hospital privacy curtains are contaminated in the first week of use. Subsequently, healthcare workers touch curtains after hand washing, and then touch the patients. The curtains become a vehicle for hospital cross infection. A durable antimicrobial function on the surface of privacy curtains can help decrease the possibility of cross-infection in hospitals. **The ultimate goal of this research is to develop novel approaches to durably and efficiently modify the surface of chemically inert polymeric materials for biomedical and medical applications with minimal impact on the physical properties. Within the previous NSERC DISCOVERY program, our research group has successfully developed a new non-destructive and effective surface modification technique for chemically inert thermoplastic polymers such as poly(ethylene terephthalate) (PET): surface modification by forming an interpenetrating network (IPN) of functional and substrate polymers. Such surface modification is durable except if the substrate polymer is dissolved or melted. This novel surface modification technique is easy-to-use, versatile (applicable on many thermoplastic polymers), has preserved mechanical strength of modified polymer substrates, and can achieve a high density of surface functional groups. Although the tensile strength of modified PET fabrics is well preserved, the flexibility of the modified substrate is compromised to a certain degree. To optimize the surface modification and minimize the negative impact on the flexibility of polymer substrates, essential for certain medical applications such as vascular grafts and wound care dressing, we propose to conduct fundamental research to characterize the interpenetrating network in a 3-dimensional fashion, to gain a deeper understanding of the process-structure-property relationship and to durably interlock the functional polymers (such as antibacterial polymers) onto thermoplastic polymers with a minimum of crosslinking. In addition, we will identify strategies to achieve more effective and selective antibacterial activity on medical textiles and implants, allowing fast inactivation of bacteria on medical textiles, and efficient and selective kill of bacteria on implants with minimum human cell toxicity. **We anticipate that the proposed study will lead to a breakthrough in the science of surface modification of chemically inert thermoplastic polymers used as medical textiles, biomaterials, and medical devices. The results from this work can be used as tools for biomaterial scientists to devise next-generation biomaterials that can better meet the biological challenges at the tissue/blood-material interface and provide technical support to industries making personal protective equipment, biomaterials and medical devices. The study of strategies for achieving more effective antibacterial surfaces will lay a foundation for the fabrication of potent and selective biocidal PET and polyurethane used in privacy curtains, nurse uniforms and surgical drapes to minimize cross-infection, and in endoscopes and catheters for biofilm control. The proposed work will lead to the training of highly qualified personnel with interdisciplinary skills in Polymer Chemistry, Analytic Chemistry, Medical Textile and Biomaterial Science.