次氯酸(HOCl)是一种由过氧化氢和氯离子在髓过氧化物酶(MPO)催化作用下产生的活性氧。由于其在机体抵抗病原体的免疫防御中起着至关重要的作用, 因此对HOCl的识别和检测具有非常重要的意义。目前, 检测HOCl的方法有电分析法、色谱法、化学发光法和荧光分析法, 其中荧光检测法以其简单、快速、高选择性、高灵敏度和实时检测等突出优点引起了许多研究者的兴趣。本文以亚甲基蓝(Methylene blue, MB)为荧光母核, 设计合成了一种近红外荧光探针MB-1用于HOCl的特异性检测。该探针可在体外特异性检测HOCl, 响应之后, 荧光会有显著的增强, 同时伴有溶液颜色从无色到蓝色的明显变化。该探针对HOCl具有较高的灵敏度, 其检测限为8.2 nmol/L。此外, 该探针具有较好的抗干扰能力, 为在生理水平上检测HOCl提供了可能。

Hypochlorous acid (HOCl) is a reactive oxygen species produced by hydrogen peroxide and chloride ions under the catalysis of myeloperoxidase (MPO). HOCl plays an important role in immune defense against pathogens. Therefore, it is of great significance to sense and detect HOCl. There are several methods for the detection of HOCl, such as electroanalysis, chromatography, chemiluminescence and fluorescence analysis and so on. Currently, fluorescence imaging technique has attracted many researchers interest because of its advantages, including high selectivity and sensitivity, easy operation, quick response, and real-time detection. In this paper, a methylene blue-based near-infrared fluorescence probe MB-1 was designed and synthesized for the fast and specific detection of HOCl. The probe can specifically detect HOCl in vitro, accompanied by a significant enhancement of near-infrared fluorescence intensity and a remarkable colour change from colorless to blue. Moreover, the probe displayed high sensitivity towards HOCl and limit of detection (LOD) was as low as 8.2 nmol/L. In addition, the probe showed good anti-interference ability, indicating that it has the potential to detect HOCl at a physiological level.