新型荧光/EPR双功能次氯酸探针的构建及性能

Novel Fluorescent/EPR Difunctional Probe for Detecting Hypochlorite

构建了一种新型香豆素-萘酰亚胺荧光/电子顺磁共振双功能探针CNNOH,并结合荧光光谱、电子顺磁共振(EPR)波谱和紫外-可见吸收光谱对其性能进行了研究.结果表明,该探针可结合荧光光谱的灵敏性和EPR波谱的特异性进行次氯酸的检测;由于香豆素与萘酰亚胺之间存在荧光共振能量转移(FRET)效应,探针分子具有较大的Stokes位移(135 nm),可有效避免由激发光导致的杂散光对检测的干扰.该双功能探针具有检出限低(0.214μmol/L)、反应速度快(~10 s)、检测范围宽(0~5 mmol/L)、选择性好及在生理条件下稳定的特点,预期在活体细胞检测方面有良好的应用前景.

To detect hypochlorite effectively and multimodally in biological system,a novel fluorescence/EPR dual probe CNNOH was designed and synthesized based on coumarin and naphthalimide derivatives. The physicochemical properties of CNNOH and its reaction with hypochlorite were studied in detail by fluorescence,electron paramagnetic resonance（ EPR） and ultraviolet-visible spectroscopies. The results showed that hypochlorite can be detected using CNNOH by fluorescence and EPR spectroscopies with integrated advantages of both techniques. Owing to fluorescence resonance energy transfer（ FRET） effect between the two fluorophores,the probe exhibits a large Stokes shift（ 135 nm） and thus effectively eliminates interference from of stray light.This dual probe has multiple advantages,such as low detection limit（ 0. 214 μmol/L）,short response time to hypochlorite（ ca. 10 s）,measurement of hypochlorite over a wide range of concentrations（ 0—5 mmol/L） as well as good selectivity and stability of CNNOH under physiological conditions. Therefore,the new probe shows great potentials in detecting or imaging hypochlorite in living cells and this molecular design provides new insights into the development of new probes for hypochlorite.