In the present study, a highly efficient electrochemical sensor for methadone measurement through the use of a glassy carbon electrode modified with two layers of graphene/Ag nanoparticles ((Gr/AgNPs)₂/GCE) nanocomposite is introduced. The morphological, elemental and electrochemical properties of the as-prepared nanocomposite were evaluated by scanning electron microscopy, energy dispersive spectroscopy. The influence of different experimental parameters such as pH and scan rate on the voltammetric response of methadone was also addressed. Exhibiting a peak potential at + 0.79 V (vs. Ag/AgCl), the as-prepared electrode manifested an improvement in its catalytic activity toward methadone oxidation. Under optimal conditions, the developed sensor exhibited an excellent response toward methadone in the concentration range of 1.0–200.0 µM with a detection limit of 0.12 µM. Moreover, the proposed electrode offered superior selectivity for methadone reflecting its efficiency for the real samples such as human blood serum.

在本研究中，通过使用两层石墨烯/银纳米粒子 ((Gr/AgNPs) ₂/GCE) 纳米复合材料。通过扫描电子显微镜、能量色散光谱评估所制备的纳米复合材料的形态、元素和电化学性能。还讨论了不同实验参数（如 pH 值和扫描速率）对美沙酮伏安响应的影响。所制备的电极在 + 0.79 V（相对于 Ag/AgCl）时表现出峰值电位，表明其对美沙酮氧化的催化活性有所提高。在最佳条件下，开发的传感器在 1.0-200.0 µM 的浓度范围内对美沙酮表现出出色的响应，检测限为 0.12 µM。此外，所提出的电极对美沙酮提供了卓越的选择性，反映了其对真实样品（如人血清）的效率。