氮掺杂石墨烯量子点/细菌纤维素复合膜的制备及应用

Preparation and Application of Nitrogen-Doped Graphene Quantum Dot/Bacterial Cellulose Composite Membrane

以一水合柠檬酸和尿素为前驱体,采用一步水热法制备出具有良好水溶性和荧光性能的氮掺杂石墨烯量子点（N-GQDs）。以细菌纤维素（BC）为基体,采用原位浸渍的方法制备出了N-GQDs/BC复合膜。通过紫外-可见光谱仪、X射线衍射仪、傅里叶变换红外光谱仪、荧光光谱仪、透射电子显微镜对N-GQDs的结构和性能进行了表征,开发出一种绿色简单的荧光生物传感器并用于多巴胺（DA）的敏感检测。结果表明：N-GQDs/BC复合膜的荧光强度能有效地被DA猝灭,且DA浓度在0~100μmol/L的范围内呈现出很好的线性关系,检测限为3.3×10^（-8）mol/L;通过分析淬灭机制证明了荧光猝灭是由于电子转移导致的。

Nitrogen-doped graphene quantum dots （N-GQDs） with good water-solubility and fluorescent properties was prepared by one-step hydrothermal method using citric acid and urea as precursors. Bacteri- al cellulose （BC）/N-GQDs composite membranes were prepared by immersing in situ. The structure and properties of N-GQDs were characterized by UV-Vis spectroscopy, X-ray diffraction, Fourier transform in- frared spectroscopy, fluorescence spectroscopy and transmission electron microscopy. A green and simple fluorescent biosensor was established and used for sensitive detecting dopamine （DA）. The results showed that the fluorescence intensity of N-GQDs/BC composite membrane could be effectively quenched by DA. A good linear correlation was observed when the DA concentration was in the range of 0×100 μmol/L, with a low detection limit of 3.3× 10-8 mol/L. It is proved that thefluorescence quenching is due to electrons trans- fer.