EDTA-Functionalized
Carbon Dots–Metal Nanozymes
Based on Coordination Chemistry: Species of Metal Ions Determines
Enzyme-Mimicking Catalyzed Activities
posted on 2024-02-26, 13:35authored byJiaxin Dong, Guanxiong Liu, Yuri V. Petrov, Yujie Feng, Dechang Jia, Vladimir E Baulin, Aslan Yu Tsivadze, Yu Zhou, Baoqiang Li
Metal ion-carbon based nanomaterials
served as nanozymes
to mimic
the biocatalytic performance of natural enzymes. However, there are
still challenges in constructing carbon dots (CDs)–metal nanozymes
with the same coordination structure based on coordination chemistry
and revealing the effect of metal ion species on enzyme-mimicking
catalyzed activities. Herein, EDTA-functionalized carbon dots–metal
(CDsEDTA-Me) nanozymes with different metal ions (Fe3+, Cu2+, and Co2+) and the same coordination
structures are synthesized based on coordination chemistry. Species
of metal ions of CDsEDTA-Me nanozymes determines enzyme-mimicking
activities. CDsEDTA-Fe, CDsEDTA-Cu, and CDsEDTA-Co display significant peroxidase (POD)-mimicking, superoxide
dismutase (SOD)-mimicking activities, and hydroxyl radical (•OH)
scavenging ability, respectively. Compared with horseradish peroxidase,
the affinity of CDsEDTA-Fe to H2O2 is improved by 47 times. The Vm value
of CDsEDTA-Fe with TMB as the substrate is 1.19 ×
10–7 M s–1. POD-mimicking activity
of CDsEDTA-Me nanozymes increases linearly with the increase
of stability constants of CDsEDTA-Me, which indicates that
the POD-mimicking activity of CDsEDTA-Me can be predicted
by stability constants of CDsEDTA-Me. CDsEDTA-Me provides a coordination chemistry strategy for the construction
of CDs-metal nanozymes and rational improvement of enzyme-mimicking
activities.