College of Chemical Engineering and Materials Science, Tianjin University of Science & Technology, Tianjin, 300457, PR China.
College of Chemical Engineering and Materials Science, Tianjin University of Science & Technology, Tianjin, 300457, PR China.
Carbohydr Polym. 2019 Apr 1;209:258-265. doi: 10.1016/j.carbpol.2019.01.023. Epub 2019 Jan 9.
The present work describes the comparison of the abilities of graphene-cyclodextrin conjugates to enhance the electrochemical performance of four tyramine-related compounds. First, cyclodextrin (CD)-modified graphene conjugates were synthesized via the amine-epoxy reaction between graphene oxide (GO) and 6-deoxy-6-ethylenediamino-β-CD, followed by l-ascorbic acid reduction. The resulting conjugates were characterized using UV-vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Subsequently, for the comparative study, glass carbon electrode electrochemical sensors modified with these conjugates were prepared to detect four structurally similar analytes (tyramine, l-tyrosine, dopamine and levodopa). The sensor sensitivities of the modified electrodes were markedly higher than that of the bare electrode. Based on the results of the comparative study, several crucial factors for improving the performance of the electrodes were proposed, including the binding affinity and the binding orientation of CD toward analytes. The conclusions drawn in this study could provide theoretical foundation for the design and optimization of versatile electrochemical platforms with excellent properties.
本工作描述了石墨烯-环糊精缀合物增强四种酪胺相关化合物电化学性能的能力比较。首先，通过氧化石墨烯（GO）与 6-脱氧-6-乙二胺基-β-CD 之间的胺-环氧反应，随后进行 l-抗坏血酸还原，合成了环糊精（CD）修饰的石墨烯缀合物。使用紫外可见光谱法、傅里叶变换红外光谱（FTIR）、拉曼光谱、热重分析（TGA）、X 射线衍射（XRD）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）对所得缀合物进行了表征。随后，为了进行比较研究，制备了用这些缀合物修饰的玻璃碳电极电化学传感器来检测四种结构相似的分析物（酪胺、l-酪氨酸、多巴胺和左旋多巴）。修饰电极的传感器灵敏度明显高于裸电极。基于比较研究的结果，提出了提高电极性能的几个关键因素，包括 CD 对分析物的结合亲和力和结合取向。本研究得出的结论可为设计和优化具有优异性能的通用电化学平台提供理论基础。
