Highly Sensitive Electrochemical Detection of Acetaminophen Using a CNH/Au-CNF Modified Glassy Carbon Electrode

In this study, a novel composite electrode was developed by fabricating gold-decorated carbon nanofibers (Au-CNFs) via an electrospinning technique, followed by mixing with an equal weight of carbon nanohorns (CNHs) to modify a glassy carbon electrode (GCE). The resulting CNH/Au-CNF/GCE was employed for the highly sensitive electrochemical detection of acetaminophen (APAP). This sensor exhibited outstanding electrochemical performance, achieving high sensitivities of 28.15 μA μM −1 cm −2 and 1.37 μA μM −1 cm −2 within APAP concentration ranges of 10–100 μM and 0.1–1 μM, respectively. A low detection limit of 63 nM was achieved, along with excellent repeatability (RSD = 3.13%) and reproducibility (RSD = 1.38%), as well as a strong anti-interference capability against common coexisting substances. Material characterizations revealed that the incorporation of CNHs significantly enhanced the electroactive surface area and reduced the charge transfer resistance at the electrode–electrolyte interface. The synergistic integration of CNHs and Au-CNFs combines the high surface area and porous conductive network of CNHs with the excellent electrocatalytic activity of Au nanoparticles, thereby markedly accelerating electron transfer and enhancing APAP oxidation. The developed sensor was further validated with real samples, showing satisfactory recoveries and strong applicability in complex matrices. These results confirm its potential for practical clinical and environmental monitoring of APAP.