We demonstrate the ability of a sensor containing a tethered fluorescein-phenol structure to react with peroxyl radicals and with an oxidizing agent such as potassium ferricyanide. This latter reaction yields the corresponding peroxyl radical as observed by EPR analysis. We propose that the reaction of the sensor with peroxyl and alkoxyl radicals is also initiated by the formation of the phenoxyl radicals, which is followed by radical-radical reactions and product hydrolysis responsible for the release of fluorescein. The proposed mechanism is based on results obtained by laser flash photolysis, HPLC and EPR studies of the reaction of peroxyl and alkoxyl radicals with 4-phenoxylphenol, a molecule used to mimic the behavior of the sensor.

中文翻译：

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基于荧光素-苯酚偶联的活性氧传感器的作用机理：以2- [6-（4'-羟基）苯氧基-3H-黄嘌呤-3-on-9-基]苯甲酸为例。

我们演示了包含系留的荧光素-苯酚结构的传感器与过氧自由基和氧化剂（如铁氰化钾）反应的能力。如EPR分析所观察到的，后一反应产生相应的过氧自由基。我们提出传感器与过氧和烷氧基的反应也通过苯氧基的形成而引发，然后自由基反应和负责荧光素释放的产物水解。所提出的机理是基于通过激光闪光光解，HPLC和EPR研究过氧自由基和烷氧基自由基与4-苯氧基苯酚（一种用于模拟传感器性能的分子）的反应而获得的结果。