基于trityl自由基的高灵敏高特异氢过硫化物EPR探针的开发及性能研究

氢过硫化物（RSSH）是最重要的活性硫（RSS）物种之一，与诸多重大疾病的发生发展密切相关。目前已有的检测方法由于普遍无法在高浓度生物巯基干扰下区分检测不同种类RSS而难以实现对RSSH的快速准确定量分析。电子顺磁共振（EPR）波谱法因其检测零背景、分析时间短及组织穿透能力优良而备受关注。本项目拟基于三苯甲基（trityl）自由基：1）对母体化合物进行卤化修饰，改变、调整trityl自由基卤化物的亲核反应活性和连接链上磁性氢原子的化学微环境，构建对RSSH具有快速、灵敏、特异检测能力的EPR探针；2）考察不同探针分子与RSSH的反应活性、响应灵敏性及特异性，筛选出性能最优的目标EPR探针；3）以小鼠巨噬细胞氧化应激模型为对象，阐明目标探针特异性检测细胞内GSSH含量及同步检测细胞内GSSH与GSH水平的实用性，为该EPR探针在与氢过硫化物相关疾病的发病机制研究与精准诊疗提供直接的实验依据。

Hydropersulfide (RSSH) is one of the most important reactive sulfur species and it has been proved to be closely associated with the occurrence and progression of various major diseases. Unfortunately, the present detection methods are difficult to afford rapid and accurate quantitative analysis of RSSH due to the inability to distinguish the reactive sulfur species in the presence of high concentration RSH. Recently, electron paramagnetic resonance (EPR) spectroscopy has attracted intense attention because of no interference from background, short analysis time and its excellent magnetic field depth of tissue penetration. Based on the tetrathiatriarylmethyl (trityl) radical, this proposal consists of three research aims: 1) After the halogenated modification of trityl parent, EPR probes with rapid, sensitive and specific detection capability for RSSH will be constructed by changing and adjusting the nucleophilic reactivity of trityl halide and the chemical microenvironment of hydrogen on the connection chain; 2) Then, the reaction activity, response sensitivity and specificity to RSSH of these probes will be investigated, and the target EPR probe with the best performance is screened out; 3) The application potential of the target EPR probe for specific quantitation of intracellular GSSH and simultaneous detectetion of GSSH and GSH will be tested in macrophage oxidative stress cell model of mouse. Overall, the RSSH EPR probe developed in this proposal will show great potential to investigate the mechanism of hydropersulfide related diseases, determine the efficacy of potential therapies and develop new therapies to study the practicability of the probe.