Xiao Pengyu, Liu Yang, Zong Wenjing, Wang Jin, Wu Minghuo, Zhan Jingjing, Yi Xianliang, Liu Lifen, Zhou Hao
Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Ocean Science and Technology, Panjin Campus, Dalian University of Technology 116023 China
College of Agriculture and Biology, Shanghai Jiao Tong University Shanghai 200240 China
RSC Adv. 2020 Feb 13;10(12):6801-6806. doi: 10.1039/c9ra10480a.
Multiple enzyme-like activities of manganese oxides (MnO) have been reported and applied in catalysis, biosensors, and cancer therapy. Here, we report that catechol can be determined colorimetrically based on the 3,3',5,5'-tetramethylbenzidine (TMB) oxidase-like activity of δ-MnO. The detection was based on pre-incubation of catechol containing water samples with δ-MnO, and then the residual TMB oxidase-like activity of reacted δ-MnO was linearly dependent on the catechol concentration in the range of 0.5 to 10 μM. This determination method was stable at pH 3.73-6.00 and was not affected by ion strength up to 200 μM. Common co-solutes in water bodies (50 μM) have negligible effects and excellent selectivity of catechol among various phenolic compounds (15 μM) was facilitated. Both reduction and aggregation of δ-MnO were observed during the incubation process with catechol, and aggregation-induced TMB oxidase-mimic activity decrease was the main factor for this colorimetric determination.
锰氧化物（MnO）的多种类酶活性已被报道，并应用于催化、生物传感器和癌症治疗领域。在此，我们报告基于δ-MnO的3,3',5,5'-四甲基联苯胺（TMB）氧化酶样活性，可通过比色法测定儿茶酚。该检测基于含儿茶酚的水样与δ-MnO预孵育，然后反应后的δ-MnO残留的TMB氧化酶样活性在0.5至10 μM范围内与儿茶酚浓度呈线性相关。该测定方法在pH 3.73 - 6.00时稳定，在高达200 μM的离子强度下不受影响。水体中的常见共溶质（50 μM）影响可忽略不计，且在各种酚类化合物（15 μM）中对儿茶酚具有出色的选择性。在与儿茶酚孵育过程中观察到δ-MnO的还原和聚集，聚集诱导的TMB氧化酶模拟活性降低是该比色测定的主要因素。
