This paper presents a novel sensor for the electrochemical detection of ephedrine (EPD), a precursor compound used in the illicit production of amphetamines and related drugs. The sensor is based on a modified glassy carbon electrode (GCE) modified with nickel oxide/nitrogen-doped graphene oxide nanocomposite (NiO/NGO). The NiO/NGO nanocomposite was created hydrothermally and examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) methods. The successful nitrogen doping of graphene oxide (GO) and the anchoring of NiO nanoparticles on GO nanosheets in the nanocomposite are confirmed by all characterization studies. Measurements using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to assess the electrochemical performance of the NiO/NGO/GCE. The NiO/NGO/GCE showed good sensitivity, stability, and selectivity for EPD detection, with a linear range of 10–2580 µM and a detection limit of 0.09 µM. Moreover, the NiO/NGO/GCE was effectively used to calculate EPD in actual blood serum samples, yielding findings that were both reproducible and adequate (the recovery values varied from 98.80% to 99.40%, and the RSD values from 3.591% to 4.21%). The suggested biosensor provides an easy, quick, and affordable way to detect EPD in sports doping control.

中文翻译：

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运动中血液兴奋剂的电化学检测：基于氧化镍/氮掺杂氧化石墨烯纳米复合材料的新型生物传感器

本文提出了一种用于电化学检测麻黄碱（EPD）的新型传感器，麻黄碱是一种用于非法生产安非他明和相关药物的前体化合物。该传感器基于用氧化镍/氮掺杂氧化石墨烯纳米复合材料（NiO/NGO）改性的改性玻碳电极（GCE）。 NiO/NGO 纳米复合材料通过水热法制备，并使用扫描电子显微镜 (SEM)、X 射线衍射 (XRD) 和 X 射线光电子能谱 (XPS) 方法进行检查。所有表征研究都证实了氧化石墨烯 (GO) 的成功氮掺杂以及纳米复合材料中 GO 纳米片上 NiO 纳米颗粒的锚定。使用循环伏安法（CV）和微分脉冲伏安法（DPV）进行测量来评估NiO/NGO/GCE的电化学性能。 NiO/NGO/GCE 对 EPD 检测表现出良好的灵敏度、稳定性和选择性，线性范围为 10–2580 µM，检测限为 0.09 µM。此外，NiO/NGO/GCE 可有效地用于计算实际血清样品中的 EPD，得出的结果具有可重复性和充分性（回收率从 98.80% 到 99.40%，RSD 值从 3.591% 到 4.21%） ）。建议的生物传感器提供了一种简单、快速且经济实惠的方法来检测运动兴奋剂控制中的 EPD。