Zhang Ensheng, Zhang Qingxiang, Li Anzhang, Lu Wenhui, Li Yuning, Li Kaiyue, Liu Xianghong, Cheng Tingting, Ju Ping, Qu Fengli
Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165, China.
Key Laboratory of Life-Organic Analysis of Shandong Province, School of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong, 273165, China.
Talanta. 2025 Jun 28;297(Pt A):128530. doi: 10.1016/j.talanta.2025.128530.
Hymexazol is extensively used as a pesticide in agriculture and may pose potential hazards to human health as well as the environment. However, fluorescent or colorimetric detection of hymexazol is rarely reported. In this study, a fluorescence carbon-dots nanozyme (Fe-SACDs-RhB) with peroxidase-like activity was derived from shikimic acid. Fe-SACDs-RhB exhibits two fluorescence emission peaks at 494 nm and 578 nm, respectively. The emission at 578 nm of Fe-SACDs-RhB was enhanced in the presence of hymexazol, while the emission at 494 nm remained unchanged to offer the ratio signal. The limit of detection (LOD) using this ratiometric fluorescence method was 0.49 μM. Moreover, Fe-SACDs-RhB could catalyze oxidation of chromogenic substrate tetramethylbenzidine (TMB) to ox-TMB in the presence of HO. ESR testing indicated that the reactive oxygen species generated by Fe-SACDs-RhB were •OH, •O, and O, with •OH being the primary product. Hymexazol can react with reactive oxygen species, thereby preventing the oxidation of TMB and leading to the decrease of absorbance at 652 nm. Therefore, Fe-SACDs-RhB was used for colorimetric detection of hymexazol based on its peroxidase-like activity with a detection limit of 1.13 μM. The feasibility of the as-developed method has been confirmed by real sample analysis in soil and water samples with good recoveries.
恶霉灵在农业中被广泛用作杀虫剂，可能对人类健康和环境构成潜在危害。然而，关于恶霉灵的荧光或比色检测报道很少。在本研究中，一种具有过氧化物酶样活性的荧光碳点纳米酶（Fe-SACDs-RhB）由莽草酸衍生而来。Fe-SACDs-RhB分别在494nm和578nm处呈现两个荧光发射峰。在恶霉灵存在下，Fe-SACDs-RhB在578nm处的发射增强，而在494nm处的发射保持不变，从而提供比率信号。采用这种比率荧光法的检测限为0.49μM。此外，在HO存在下，Fe-SACDs-RhB可以催化显色底物四甲基联苯胺（TMB）氧化为ox-TMB。电子顺磁共振测试表明，Fe-SACDs-RhB产生的活性氧物种为•OH、•O和O，其中•OH是主要产物。恶霉灵可以与活性氧物种反应，从而阻止TMB的氧化，并导致652nm处吸光度降低。因此，基于其过氧化物酶样活性，Fe-SACDs-RhB被用于恶霉灵的比色检测，检测限为1.13μM。通过对土壤和水样的实际样品分析，回收率良好，证实了所开发方法的可行性。
