A glassy carbon electrode modified with N-doped carbon dots for improved detection of hydrogen peroxide and...

Nitrogen doped carbon dots (NCDs) were synthesized using a low temperature approach and used to modify a glassy carbon electrode (GCE) via dipping. The oxygen groups on the surface of the NCDs, and the charge delocalization of the NCDs warrant an excellent electrocatalytic activity of the GCE toward oxidation of paracetamol (PA) and reduction of H₂O₂. PA and H₂O₂ were detected at 0.34 V and -0.4 V (both vs. Ag/AgCl) using differential pulse voltammetry and amperometric I-T measurement, respectively. The modified GCE has a linear response to PA in the 0.5 to 600 μM concentration range, and to H₂O₂ in the 0.05 μM to 2.25 mM concentration range. The detection limits are 157 nM and 41 nM, respectively. In our perception, the modified GCE holds promise for stable, selective and sensitive determination of PA and H₂O₂ in pharmaceutical analysis. Graphic abstract Nitrogen doped carbon dots (NCDs) were synthesized and used to modify a glassy carbon electrode. Surface functional groups on NCDs can trigger electrocatalytic reactions toward paracetamol oxidation and H₂O₂ reduction with high sensitivities.