AuNPs-NH2/Cu-MOF modified glassy carbon electrode as enzyme-free electrochemical sensor detecting H2O2

Abstract

Hydrogen peroxide (H2O2) plays an important role in physiological processes. In this work, a Cu-based metal-organic framework (Cu-MOF) was synthesized under ionothermal condition, further grafted with ammoniated Au nanoparticles (AuNPs-NH2) to prepare AuNPs-NH2/Cu-MOF composite. Glassy carbon electrode (GCE) was modified with AuNPs-NH2/Cu-MOF to prepare AuNPs-NH2/Cu-MOF/GCE electrode, which was used in H2O2 detection. AuNPs-NH2/Cu-MOF/GCE exhibits itself as a highly sensitive and selective electrochemical enzyme-free sensor for H2O2 detection. A quantitative detection to H2O2 can be found with a wide linear response toward H2O2 concentrations ranging 5–850 μM, its limit of detection (LOD) is as low as 1.2 μM with a high sensitivity of 1.71 μA/cm2·μM. AuNPs-NH2/Cu-MOF/GCE sensor has been applied to determine H2O2 effectively in human cervical cancer cells by adding the ascorbic acid as the stimulant. Our work presented a AuNPs-NH2/Cu-MOF/GCE composite electrode which is a promising enzyme-free electrochemical sensor for quantitive H2O2 detection in human cervical cancer cells.