Synthesis of new copper nanoparticle-decorated anchored type ligands: Applications as non-enzymatic electrochemical sensors for hydrogen peroxide

In this work, copper nanoparticles (CuNPs) decorated on two new anchored type ligands were utilized to prepare two electrochemical sensors. These ligands are made from bonding amine chains to silica support including SiO2–pro–NH2 (compound I) and SiO2–pro–NH–cyanuric–NH2 (compound II). The morphology of synthesized CuNPs was characterized by transmission electron microscopy (TEM). The nano-particles were in the range of 13–37nm with the average size of 23nm. These materials were used to modify carbon paste electrode. Different electrochemical techniques, including cyclic voltammetry, electrochemical impedance spectroscopy and hydrodynamic chronoamperometry, were used to study the sensor behavior. These electrochemical sensors were used as a model for non-enzymatic detection of hydrogen peroxide (H2O2). To evaluate the abilities of the modified electrodes for H2O2 detection, the electrochemical signals were compared in the absence and presence of H2O2. From them, two modified electrodes showed significant responses vs. H2O2 addition. The amperograms illustrated that the sensors were selective for H2O2 sensing with linear ranges of 5.14–1250μmolL−1 and 1.14–1120μmolL−1 with detection limits of 0.85 and 0.27μmolL−1 H2O2, sensitivities of 3545 and 11,293μAmmol−1L and with response times less than 5s for I/CPE and II/CPE, respectively. As further verification of the selected sensor, H2O2 contained in milk sample was analyzed and the obtained results were comparable with the ones from classical control titration method. [Display omitted] •Copper nanoparticles decorating on two new anchored type ligands were prepared.•Ligands are bonding to silica support as SiO2–pro–NH2 and SiO2–pro–NH–cyanuric–NH2.•These materials were used as electrochemical sensors for H2O2 detection.•H2O2 could be detected as low as 0.27μmolL−1.