Novel Spin Traps for Biological Free Radical Detection

描述(申请人提供)：在过去的二十年里，在生理条件下，活性氧被认为是氧化过程和疾病机制的关键介质。因此，在从化学反应到酶反应以及从细胞到活体的各种系统中，拥有一种能够识别形成部位的自由基的直接技术至关重要，以便能够理解生物系统中潜在的氧化损伤的机制和过程。这项提议的总体目标是开发具有改进性质的新型自旋陷阱，可用于利用电子顺磁共振(EPR)光谱研究生物系统中的氧化应激。···还是RS？这是通过它们在加入自旋陷阱形成持久的自由基加合物后给出的独特的EPR光谱轮廓实现的。目前最常用的自旋捕捉剂5，5-二甲基-1-吡咯啉N-氧化物(DMPO)、二乙氧基磷酰基-5-甲基-1-吡咯啉N-氧化物(DEPMPO)和5-乙氧羰基-5-甲基-1-吡咯啉N-氧化物(EMPO)都存在捕获超氧阴离子效率低、生物环境中自由基加合物半衰期短、细胞毒性、敏感性和靶向性差等缺点。我们的目标是通过在自旋陷阱开发中采用跨学科的方法来克服这些限制，该方法包括理论预测、有机合成、动力学测定、毒性，并最终通过实验应用来识别和检测体外和体内系统中自由基形成的位置。这些技术的协同应用将提供一种最佳的策略，以提供新的材料，这些材料可以有效地探索活性氧在生物机制中的作用。

DESCRIPTION (provided by applicant): Over the past two decades, reactive oxygen species have been implicated as critical mediators of oxidative processes and disease mechanisms under physiological conditions. Therefore, it is of critical importance to have a direct technique capable of identifying free radicals at their site of formation in systems ranging from chemical to enzymatic reactions, and cellular to in vivo systems so that the mechanisms and processes underlying the oxidative damage in biological systems can be understood. The overall objective of this proposal is to develop novel spin traps with improved properties that can be applied to study oxidative stress in biological systems using electron paramagnetic resonance (EPR) spectroscopy. The specific monitoring of the formation of biologically relevant reactive oxygen species such as ?OH, O2?-, ROO? or RS? is achieved by the distinctive EPR spectral profile they give after addition to spin traps to form a persistent radical adduct. The most commonly used spin traps, 5,5-dimethyl-1-pyrroline N-oxide (DMPO), diethoxyphosphoryl-5-methyl-1-pyrroline N-oxide (DEPMPO) and 5-ethoxycarbonyl-5-methyl-1-pyrroline N-oxide (EMPO), are limited by their poor efficiency of trapping superoxide radical anion, short half-life of the radical adduct formed in biological milieu, cytotoxicity, sensitivity and target specificity. Our aim is to overcome such limitations by employing an interdisciplinary approach in spin trap development that encompasses theoretical prediction, organic synthesis, kinetic determination, toxicity, and ultimately, their experimental application to identify and detect free radical formation in in vitro and in vivo systems at their site of formation. The synergistic application of these technologies will provide an optimal strategy to provide new materials which can be effective in probing the role of reactive oxygen species in biological mechanisms.