Herein, a rapid and highly sensitive amperometric biosensor for the detection of α-ketoglutarate (α-KG) was constructed via an electrochemical approach, in which the glutamate dehydrogenase (GLUD) was modified on the surface of reduced graphene oxide-gold nanoparticle composite (rGO-Au_nano composite). The rGO-Au_nano composite was one-step electrodeposited onto glassy carbon electrode (GCE) surface and was characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and electrochemical techniques. In addition, the rGO-Au_nano/GCE was also found to electrocatalyze the oxidation of β-nicotinamide adenine dinucleotide (NADH) at the peak potential of 0.3 V, which was negatively shifted compared with that at bare GCE or Au_nano/GCE, illustrating better catalytic performance of rGO-Au_nano. After the modification of GLUD, the GLUD/rGO-Au_nano/GCE led to effective amperometric detection of α-KG through monitoring the NADH consumption and displayed a linear response in the range of 66.7 and 494.5 μM, with the detection limit of 9.2 μM. Moreover, the prepared GLUD/rGO-Au_nano/GCE was further evaluated to be highly selective and used to test α-KG in human serum samples. The recovery and the RSD values were calculated in the range of 97.9–102.4% and 3.8–4.5%, respectively, showing a great prospect for its real application.

中文翻译：

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基于还原氧化石墨烯-金纳米复合材料的高灵敏度安培α-酮戊二酸生物传感器。


在此，通过电化学方法构建了一种快速、高灵敏度的用于检测α-酮戊二酸（ α -KG）的电流生物传感器，其中谷氨酸脱氢酶（GLUD）被修饰在还原氧化石墨烯-金纳米颗粒复合物的表面（ rGO-Au_纳米复合材料）。 rGO-Au_纳米复合材料被一步电沉积到玻碳电极（GCE）表面，并通过扫描电子显微镜（SEM）、能量色散X射线光谱（EDS）和电化学技术进行表征。此外，还发现rGO-Au _nano /GCE在0.3 V的峰值电位下电催化β-烟酰胺腺嘌呤二核苷酸（NADH）的氧化，与裸GCE或Au _nano /GCE相比出现负移，说明rGO-Au_纳米具有更好的催化性能。 GLUD修饰后，GLUD/rGO-Au _nano /GCE通过监测NADH消耗，实现对α -KG的有效安培检测，并在66.7和494.5 μM范围内呈现线性响应，检测限为9.2此外，进一步评估制备的GLUD/rGO-Au _nano /GCE具有高选择性，并用于测试人血清样品中的α -KG。计算回收率和RSD值分别在97.9%~102.4%和3.8%~4.5%范围内,显示出其实际应用的良好前景。