Research Supplement to Promote Diversity Supplement for the ECMO without Anticoagulation

项目总结/摘要 一氧化氮（NO）是一种由内皮细胞一氧化氮持续产生的气态自由基 血管壁内的内皮型一氧化氮合酶（eNOS）酶，是一种重要的分子， 维持体内平衡并防止血栓形成。NO是一种非常活泼的分子， 半衰期仅为2 ms，可在血液中形成各种代谢物。血液的人造表面 接触装置可激活血小板并诱导血栓形成。这是一个不希望的 体外循环生命支持（ECLS）回路的副作用，通常通过全身性 抗凝，但这会增加出血并发症的风险。因此，有一个 努力创造更多的生物相容性人造表面， 抗凝 无排放人造表面提供了有吸引力的解决方案，这个问题。然而， 这样的表面固有地受到限制。 在本研究补充中，我们想探索一种替代方法， NO有效负载以NO代谢物的形式在血液中循环（例如，亚硝酸盐，小， 大分子量的S-亚硝基硫醇）作为储库，并在与 生物医学装置的化学改性人工表面。我们希望实现这一目标 通过以下目标： 目的1：开发分析方法来测量血液中的循环NO供体。 将开发选择性分析方法来量化潜在的循环NO供体（亚硝酸盐， 小分子量和大分子量S-亚硝基硫醇）。 目的2：调节血液中循环NO库的浓度。这一目标是 评估输送的NO气体对体内单个NO代谢物的量的影响， 血NO气体将通过体外膜式氧合器输送至预处理血液 setup.这将允许精确控制NO向血液的递送（NO和NO的分压）。 O2，吹扫气体和血液的流速）。 目的3：修改EC表面，可以诱导NO释放循环NO水库。 我们将用二价金属离子掺杂/共价改性的聚合物涂层涂覆PVC管 (Cu2+），并评估其诱导NO从循环NO库中释放的能力， 在体外钱德勒袢模型中的血凝块形成。

PROJECT SUMMARY/ABSTRACT Nitric Oxide (NO) is a gaseous radical continuously produced by the endothelial nitric oxide synthase (eNOS) enzyme within the walls of the blood vessels and is an essential molecule to maintain homeostasis and prevent blood clot formation. NO is an extremely reactive molecule with only 2 ms half-life and can form various metabolites in the blood. The artificial surfaces of blood contacting devices can activate platelets and induce thrombus formation. This is a not desired side effect of Extracorporeal Life Support (ECLS) circuits and is typically prevented by systemic anticoagulation, which however increases the risk of hemorrhagic complications. Hence, there is an effort to create more biocompatible artificial surfaces that obviate the need for systemic anticoagulation. NO emitting artificial surfaces offer attractive solution to this problem. However, the NO payload of such surfaces is inherently limited. In this research supplement we would like to explore an alternative approach, where the available NO payload is circulating within the blood in the form of NO metabolites (e.g., nitrite, small and large molecular weight S-nitroso thiols) as reservoirs and is released upon contact with the chemically modified artificial surface of the biomedical device. We would like to achieve this goal through the following aims: Aim 1: Develop analytical methods to measure circulating NO donors in the blood. Selective analytical methods will be developed to quantify potential circulating NO donors (nitrite, small and large molecular weight S-nitroso thiols) in the blood. Aim 2: Modulate concentration of circulating NO reservoirs in the blood. This aim is to assess the effect of the delivered NO gas on the quantity of individual NO metabolites within the blood. NO gas will be delivered to pre-conditioned blood via an in vitro membrane oxygenator setup. This will allow for precise control of the delivery of NO to the blood (partial pressure of NO and O2, flow rate of sweep gas and blood). Aim 3: Modify EC surfaces that can induce NO release from circulating NO reservoirs. We will coat PVC tubing with a polymer coating doped/covalently modified with divalent metal ions (Cu2+) and assess its ability to induce NO release from the circulating NO reservoirs and to prevent blood clot formation in vitro in Chandler loop model.