Abstract：
A solvothermal synthesis of ultrasmall cerium oxide nanoparticles (USCeOxNPs) with an average size of 0.73 ± 0.07 nm using deep eutectic solvent (DES) as a stabilizing medium at a temperature of 90 ºC is reported. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) were used to morphologically characterize the USCeOxNPs. These revealed approximately spherical shapes with emission lines characteristic of cerium. Selected area electron diffraction (SAED) was used to determine the crystalline structure of the cerium oxide nanoparticles (CeO2NPs), revealing the presence of crystalline cubic structures. The USCeOxNPs-DES/CB film was characterized by scanning electron microscopy (SEM), which demonstrated the spherical characteristic of CB with layers slightly covered by DES residues. DES was characterized by Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR), indicating its formation through hydrogen bonds between the precursors. An electrochemical sensor for dopamine (DA) determination in biological fluids was developed using the USCeOxNPs together with carbon black (CB). An enhanced current response was observed on DA voltammetric determination, and this can be attributed to the USCeOxNPs. This sensor displayed linear responses for DA in the range 5.0 × 10-7 mol L-1 to 3.2 × 10-4 mol L-1, with a limit of detection of 80 nmol L-1. Besides detectability, excellent performances were verified for repeatability and anti-interference. The sensor based on USCeOxNPs synthesized in DES in a simpler and environmentally friendly way was successfully applied to determine DA in biological matrix.
摘要：
据报道，在90ºC的温度下，使用深共熔溶剂（DES）作为稳定介质，溶剂热合成平均尺寸为0.73±0.07nm的超小氧化铈纳米颗粒（USCeOxNPs）。透射电子显微镜（TEM）和能量色散光谱（EDS）用于对USCeOxNP进行形态学表征。这些显示出具有铈的发射线特征的近似球形。选择面积电子衍射（SAED）用于确定氧化铈纳米颗粒（CeO2NP）的晶体结构，揭示了结晶立方结构的存在。通过扫描电子显微镜(SEM)对USCeOxNPs-DES/CB薄膜进行了表征,证明了CB的球形特征，该层被DES残基略微覆盖。通过傅里叶变换红外(FT-IR)和核磁共振(NMR)对DES进行了表征,表明它通过前体之间的氢键形成。使用USCeOxNP和炭黑（CB）开发了用于生物流体中多巴胺（DA）测定的电化学传感器。在DA伏安测定中观察到增强的电流响应，这可以归因于USCeOxNP。该传感器对DA的线性响应范围为5.0×10-7molL-1至3.2×10-4molL-1，检测限为80nmolL-1。除了可检测性，具有良好的重复性和抗干扰性。基于在DES中以更简单，环保的方式合成的USCeOxNPs的传感器已成功应用于测定生物基质中的DA。
