A new biosensor for detecting l-glutamate (l-Glu) in beef was developed. Firstly, a bare Au electrode was surface-modified by gold nanoparticles (Au NPs), graphene oxide (GO), and chitosan (CS) as immobilized materials, and then its surface was connected with l-glutamate oxidase (GluOx). The modified Au NPs/GO/CS electrode was characterized by scanning electron microscopy, and the formation mechanism was elaborated. The response current of the l-Glu biosensor maximized to 0.08 mA at pH 7.5 and 0.09 mA at 30 °C, with a detection range of 0.2–1.4 mM and a detection limit of 0.023 mM. The l-Glu biosensor had high accuracy, and its results linearly fitted with those of the amino acid analyzer with a coefficient of 0.996. The l-Glu biosensor had high selectivity, repeatability, and stability and detected higher l-Glu content in the cooked beef than in the raw beef.

用于检测新的生物传感器升谷氨酸盐（升牛肉-Glu）的开发。首先，用金纳米颗粒（Au NPs），氧化石墨烯（GO）和壳聚糖（CS）作为固定材料对裸露的Au电极进行表面改性，然后将其表面与1-谷氨酸氧化酶（GluOx）连接。通过扫描电子显微镜对修饰的金纳米粒子/ GO / CS电极进行了表征，并详细阐述了其形成机理。l -Glu生物传感器的响应电流在pH 7.5时最大为0.08 mA，在30°C时最大为0.09 mA，检测范围为0.2–1.4 mM，检测极限为0.023 mM。该升-Glu生物传感器具有很高的准确性，其结果与氨基酸分析仪的结果线性拟合，系数为0.996。所述1 -Glu生物传感器具有高选择性，可重复性和稳定性，并且在煮熟的牛肉中比生牛肉中检测到更高的1 -Glu含量。