Novel Spin Traps for Biological Free Radical Detection

描述（由申请人提供）：在过去二十年中，活性氧被认为是生理条件下氧化过程和疾病机制的关键介质。因此，至关重要的是要有一个直接的技术，能够识别自由基在其形成的网站系统，从化学到酶反应，细胞在体内系统，使生物系统中的氧化损伤的机制和过程可以理解。该提案的总体目标是开发具有改进性能的新型自旋陷阱，其可应用于使用电子顺磁共振（EPR）光谱研究生物系统中的氧化应激。生物学相关活性氧簇形成的具体监测，如？哦，氧气？-，ROO？RS？通过加入自旋陷阱形成持久自由基加合物后得到的独特EPR光谱曲线实现。最常用的自旋捕集剂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）由于捕集超氧阴离子自由基的效率低、自由基加合物在生物环境中的半衰期短、细胞毒性、灵敏度和靶点特异性而受到限制。我们的目标是克服这种限制，采用跨学科的方法在自旋陷阱的发展，包括理论预测，有机合成，动力学测定，毒性，并最终，其实验应用，以确定和检测自由基的形成在体外和体内系统在其网站的形成。这些技术的协同应用将提供一种最佳策略，以提供新的材料，可以有效地探测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.