College of Chemistry and Engineering, Yangzhou University, Yangzhou 225002, PR China; College of Textiles and Clothing, Yancheng Institute of Technology, Yancheng 224051, PR China; Jiangsu Collaborative Innovation Center for Ecological Building Materials and Environmental Protection Equipments, Yancheng Institute of Technology, Yancheng 224051, PR China.
College of Chemistry and Engineering, Yangzhou University, Yangzhou 225002, PR China; Jiangsu Collaborative Innovation Center for Ecological Building Materials and Environmental Protection Equipments, Yancheng Institute of Technology, Yancheng 224051, PR China.
Talanta. 2019 May 15;197:622-630. doi: 10.1016/j.talanta.2018.12.090. Epub 2018 Dec 26.
A novel NH voltammetric electrochemical biosensor was constructed by immobilizing glutamate dehydrogenase (GLDH)/FeO/graphene (GR)/chitosan (CS) nanobiocomposite onto a glassy carbon electrode (GCE). On the GLDH/FeO/GR/CS/GCE, GLDH catalyzed the reversible reaction, i.e., the reductive amination of α-ketoglutaric acid and the oxidative deamination of L-glutamate. The electrons produced in the enzymatic reactions were transferred to the surface of the electrode via the [Fe(CN)] couple, which helped for the amplification of the electrochemical signal. The electrochemical detection of NH was based on the fact that the enhanced response current was proportional to the NH concentration. Owing to the combination of the advantages of the synergistic effects of FeO nanospheres, GR and CS, a promising platform for NH sensing was provided. Under optimum conditions, the introduced biosensor had a linear range of 0.4-2.0 μM for NH with the detection and quantification limits of 0.08 and 0.27 μM, respectively. Moreover, the biosensor exhibited good sensitivity and excellent reproducibility. It could retain 91.8% of its original response after two weeks of storage at 4 °C, suggesting satisfactory stability. Additionally, the proposed biosensor was successfully applied to detect NH levels in PM samples, indicating its feasibility for application in NHmonitoring in the environmental fields.
一种新型的 NH 伏安电化学生物传感器通过将谷氨酸脱氢酶（GLDH）/FeO/石墨烯（GR）/壳聚糖（CS）纳米生物复合材料固定在玻碳电极（GCE）上构建而成。在 GLDH/FeO/GR/CS/GCE 上，GLDH 催化了可逆反应，即α-酮戊二酸的还原氨化和 L-谷氨酸的氧化脱氨。酶反应中产生的电子通过[Fe(CN)] 配合物转移到电极表面，这有助于电化学信号的放大。NH 的电化学检测基于增强的响应电流与 NH 浓度成正比的事实。由于 FeO 纳米球、GR 和 CS 的协同效应的结合，为 NH 传感提供了一个有前途的平台。在最佳条件下，引入的生物传感器对 NH 的线性范围为 0.4-2.0 μM，检测限和定量限分别为 0.08 和 0.27 μM。此外，该生物传感器具有良好的灵敏度和出色的重现性。在 4°C 下储存两周后，其原始响应保留了 91.8%，表明其稳定性良好。此外，该生物传感器成功地应用于 PM 样品中 NH 水平的检测，表明其在环境领域 NH 监测中的应用具有可行性。
