CAREER: High-Density Non-Fouling Bioactive Coatings for Processing of Biological Fluids

职业：用于生物流体处理的高密度防污生物活性涂层

• 批准号: 1553183
• 负责人: Kate Schilke
• 金额: $ 53.3万
• 依托单位: Oregon State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-02-15 至 2021-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1553183&HistoricalAwards=false
• 关键词: CAREER; Density; Non; Fouling; Bioactive

CAREER 1553183 - SchilkeBacterial sepsis is a common and life-threatening condition which kills hundreds of thousands of Americans and costs ~$20 billion every year in the U.S. alone. Sepsis is currently treated with antibiotics, but this does not remove the circulating dead bacteria and fragments of their cell membranes (endotoxin), which could cause a serious immune response. One promising method to mitigate this risk involves passing a patient's blood through a device to capture circulating endotoxin, helping to stabilize the immune system and potentially to improve their prognosis. However for this application, all materials in contact with blood must be biocompatible (i.e. resist fouling or clotting, and not induce an adverse biological response). For treatment of sepsis, surfaces must also present endotoxin-binding agents in controlled orientations and at high density. These bioactive and biocompatible coatings must be inexpensive and easy to apply to a wide range of materials, including plastics used in medical devices, needles, flexible tubing, and other associated equipment. Biocompatible and bioactive coatings could have transformative impact on the safety and efficacy of treatment of sepsis, in which even a modest improvement could result in many lives and much money saved. In other biomedical applications, the technology could also impart biological activity to a variety of other household, consumer and industrial products. The integrated educational activities of this project are expected to achieve the following benefits: (a) research concepts will be incorporated into bioengineering coursework at Oregon State (OSU) and hands-on learning modules will be adapted for OSU's STEM Academy for pre-college students and (b) the PI will work with the OSU business school to provide a summer "Entrepreneurship Boot Camp" for the group's graduate students and faculty mentors.The project's research will result in the development of high-density, non-fouling bioactive coatings (HNB's) by living polymerization from surfactant-based immobilized initiators, producing branched, hydrophilic polymer brushes on the surface. This coating, essentially an ultrathin immobilized hydrogel, will provide excellent resistance against protein adsorption and cell interactions (biocompatibility). To impart bioactivity at the hydrogel surface, a nearly-ideal bioorthogonal ligation (BOL) will be used to immobilize enzymes, peptides, polysaccharides, or other biologically active molecules at the periphery of the brush. This chemistry enables quantitative conjugation from even dilute solutions of the active molecule, allowing precise control of surface functionalization. Unreacted groups are biologically compatible and chemically inert. Economical immobilization of peptides or proteins is provided by Genetic Code Expansion (GCE), in which engineered microbes express active proteins with BOL reactive groups incorporated at genetically-controlled positions. The resulting specific immobilization of only the desired proteins from a crude cell lysate eliminates costly purification or pre-concentration steps, and guarantees that the protein is in a precisely defined orientation for maximal biological activity. Although the main objective of this work is to demonstrate biocompatible and bioactive coatings for devices to capture pathogens from blood, myriad other potential uses include safer medical devices, food processing, pharmaceutical production, active packaging, and self-cleaning fabrics, as examples.

细菌性败血症是一种常见的危及生命的疾病，每年仅在美国就有数十万美国人死亡，花费约200亿美元。败血症目前用抗生素治疗，但这不能清除循环中的死细菌及其细胞膜碎片（内毒素），这可能会引起严重的免疫反应。减轻这种风险的一种有希望的方法是使患者的血液通过一种装置来捕获循环中的内毒素，帮助稳定免疫系统并可能改善其预后。然而，对于该应用，与血液接触的所有材料必须具有生物相容性（即，抗污染或凝血，并且不会诱导不良生物反应）。为了治疗脓毒症，表面还必须以受控的方向和高密度存在内毒素结合剂。这些生物活性和生物相容性涂层必须便宜且易于应用于广泛的材料，包括用于医疗器械、针头、软管和其他相关设备的塑料。生物相容性和生物活性涂层可能对脓毒症治疗的安全性和有效性产生变革性影响，即使是适度的改善也可能导致许多生命和节省大量资金。在其他生物医学应用中，该技术还可以将生物活性赋予各种其他家用、消费和工业产品。该项目的综合教育活动预计将取得以下效益：（a）研究概念将纳入俄勒冈州（OSU）的生物工程课程，并将实践学习模块改编为OSU的STEM学院，供大学预科学生使用;（B）PI将与OSU商学院合作，提供夏季“创业靴子营”该项目的研究将通过基于表面活性剂的固定化引发剂的活性聚合，在表面产生支化的亲水聚合物刷，从而开发高密度、无污染的生物活性涂层（HNB）。这种涂层，基本上是一种固定化的水凝胶，将提供对蛋白质吸附和细胞相互作用的优异抗性（生物相容性）。为了在水凝胶表面赋予生物活性，将使用接近理想的生物正交连接（BOL）来将酶、肽、多糖或其他生物活性分子固定在刷的周边。这种化学性质使得能够从活性分子的甚至稀溶液定量缀合，从而允许精确控制表面官能化。未反应的基团具有生物相容性和化学惰性。通过遗传密码扩增（GCE）提供肽或蛋白质的经济固定化，其中工程化的微生物表达具有在遗传控制的位置处并入的BOL反应基团的活性蛋白质。所得到的仅来自粗细胞裂解物的所需蛋白质的特异性固定消除了昂贵的纯化或预浓缩步骤，并保证蛋白质处于精确限定的取向以获得最大的生物活性。虽然这项工作的主要目标是证明用于从血液中捕获病原体的设备的生物相容性和生物活性涂层，但无数其他潜在用途包括更安全的医疗设备，食品加工，制药生产，活性包装和自清洁织物。