Target-induced mimic enzyme deactivation based on mixed-node metal-organic frameworks for colorimetric assay of hydrogen sulfide

• Published in: Chinese chemical letters 2021-10, Vol.32 (10), p.3155-3158
• Main Authors: Zhou, Fenfen, Zhou, Yanli, Zhang, Jianwei, Dong, Hui, Liu, Lantao, Zhang, Yintang, Xu, Maotian
• Format: Article
• Language: English
• Subjects: Colorimetric assay; Deactivation; Hydrogen sulfide; Metal-organic frameworks; Mimic enzyme
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2021.02.053

Colorimetric sensing for hydrogen sulfide was designed by the target-induced deactivation of mixed-node Cu-Fe MOFs. [Display omitted] Accurate detection of hydrogen sulfide (H2S) is of great significance for environmental monitoring and protection. We propose a colorimetric method for the detection of H2S by the use of mixed-node Cu-Fe metal organic frameworks (Cu-Fe MOFs) as highly efficient mimic enzymes for target-induced deactivation. The Cu-Fe MOFs were synthesized by a simple solvothermal method and could catalyze the H2O2 mediated oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to oxTMB with a blue color. The presence of dissolved H2S would deactivate the mimic enzymes, and then the blue color disappeared. The mechanism of the sensor was discussed by steady-state kinetic analysis. The designed assay was highly sensitive for H2S detection with a linear range of 0−80 μmol/L and a detection limit of 1.6 μmol/L. Moreover, some potential substances in the water samples had no interference. This method with the advantages of low cost, high sensitivity, selectivity, and visual readout with the naked eye was successfully applied to the determination of H2S in industrial wastewater samples.