Glutathione (GSH), as a crucial endogenous thiol and antioxidant, plays an essential role in the biological system, and its abnormal levels are closely related to various diseases. Therefore, it continues to be of enormous significance to develop a sensitive and efficient method for the assay of GSH. Herein, we report a facile and sensitive polymer dots (PDs)-manganese dioxide (MnO₂) nanosensor for turn-on assay of GSH. In this sensing system, the PDs with strongly green fluorescence were prepared by a mild one-step method using hydroquinone and ethylenediamine as precursors, and the fluorescence of PDs can be quenched by MnO₂ nanosheets. The PDs-MnO₂ nanosensor was the turn-off state. In the presence of GSH, however, the fluorescence of the PDs-MnO₂ nanosensor can remarkably recover because MnO₂ nanosheets can be reduced into Mn²⁺ by GSH. The PDs-MnO₂ nanosensor was the turn-on state. Based on the change of the fluorescence signal from turn-off switched to turn-on, a sensitive method was successfully constructed to detect GSH. We also systematically discussed the mechanism of the PDs-MnO₂ nanosensor for GSH assay, indicating that the MnO₂ nanosheets-induced the fluorescence quenching was derived from inner filter effect (IFE). The PDs-MnO₂ nanosensor toward GSH showed a wide linear range from 0.5 to 200 μM and high sensitivity with a limit of detection of 0.10 μM. The as-developed PDs-MnO₂ nanosensor was also successfully applied to detect GSH in human serum with satisfactory results.

谷胱甘肽（GSH）作为重要的内源性硫醇和抗氧化剂，在生物系统中起着至关重要的作用，其异常水平与各种疾病密切相关。因此，开发一种灵敏而有效的GSH测定方法仍然具有极其重要的意义。在本文中，我们报告了一种用于GSH开启分析的灵敏且敏感的聚合物点（PDs）-二氧化锰（MnO ₂）纳米传感器。在该传感系统中，使用对苯二酚和乙二胺作为前体，通过温和的一步法制备了具有强烈绿色荧光的PD，并且可以通过MnO ₂纳米片淬灭PD的荧光。PDs-MnO ₂纳米传感器处于关闭状态。然而，在谷胱甘肽存在的情况下，PDs-MnO的荧光₂纳米传感器可以显着恢复，因为MnO ₂纳米片可以通过GSH还原为Mn ²⁺。PDs-MnO ₂纳米传感器处于开启状态。基于荧光信号从关闭切换到开启的变化，成功构建了一种灵敏的方法来检测GSH。我们还系统地讨论了用于GSH分析的PDs-MnO ₂纳米传感器的机理，表明MnO ₂纳米片诱导的荧光猝灭源自内部滤光效应（IFE）。朝向GSH的PDs-MnO ₂纳米传感器显示了0.5至200μM的宽线性范围和高灵敏度，检测极限为0.10μM。已开发的PDs-MnO ₂ 纳米传感器也成功地用于检测人血清中的谷胱甘肽，具有令人满意的结果。