Abstract Based on Fenton reaction without adding nanomaterials, a simple colorimetric sensor for detecting thioglycolic acid (TGA) was developed. By reducing Fe3+ ions to Fe2+ ions, TGA efficiently stimulates Fenton reaction through accelerating Fe3+/Fe2+ redox cycle. Owing to this, the accelerated decomposition of H2O2 generates more OH radicals, which cause a significant blue change in the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB). Compared with Fe3+/H2O2/TMB system, this sensor can be operated over a wider pH range from 4.0 to 8.0. The calibration curve of TGA is achieved in the concentration range of 0.046–7.37 μg mL−1 under optimized conditions, and the detection limit of TGA is 0.036 μg mL−1 (S/N = 3). This sensor has been successfully applied to the detection of TGA in cold wave lotion with recovery rates between 99.1 and 101.6%, which has broad application prospects in cosmetic analysis and environmental monitoring.

中文翻译：

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基于增强型 Fe3+ 离子 Fenton 反应的巯基乙酸比色检测

摘要 基于芬顿反应，不添加纳米材料，研制了一种简单的检测巯基乙酸（TGA）的比色传感器。通过将 Fe3+ 离子还原为 Fe2+ 离子，TGA 通过加速 Fe3+/Fe2+ 氧化还原循环有效地刺激芬顿反应。因此，H2O2 的加速分解会产生更多的 OH 自由基，从而导致 3,3',5,5'-四甲基联苯胺 (TMB) 的氧化发生显着的蓝色变化。与 Fe3+/H2O2/TMB 系统相比，该传感器可在 4.0 至 8.0 的更宽 pH 范围内运行。在优化条件下，TGA 的校准曲线在 0.046–7.37 μg mL-1 的浓度范围内实现，TGA 的检出限为 0.036 μg mL-1（S/N = 3）。该传感器已成功应用于冷波洗剂中TGA的检测，回收率在99.1-101.6%之间，