Cancer is one of the major diseases that threaten human life. Upconversion nanoparticles (UCNPs) are one of the new nanomaterials that are expected to detect and treat cancer. One-step hydrothermal method can synthesize UCNPs with controllable physical and chemical properties and low biotoxicity. In this work, oleic acid (OA) and polyethylene glycol (PEG)–modified NaGdF₄/GdF₃:Yb,Er UCNPs were synthesized by one-step hydrothermal method. And the as-prepared UCNPs were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and by using superconductor quantum interference devices (SQUID). The cytotoxicity of the modified NaGdF₄/GdF₃:Yb,Er UCNPs was evaluated. The results show that OA-modified UCNPs are hexagonal NaGdF₄ phase, and PEG-modified UCNPs is orthorhombic GdF₃ phase respectively. The particle size of OA-modified and PEG-modified UCNPs is about 15 nm and about 30 nm, respectively. The modified UCNPs have good magnetic properties and strong upconversion luminescence properties (UCL), wherein PEG-modified UCNPs perform slightly better capabilities than those of OA-modified UCNPs. When the concentration of nanoparticles increased from 62.5 to 500 μg/mL, OA-NaGdF₄:Yb,Er showed a certain cytotoxicity and exhibited dose-effect relationship. However, PEG-GdF₃:Yb,Er did not display obvious cytotoxicity. Therefore, PEG-modified UCNPs may be more suitable for application in oncology field.

癌症是威胁人类生命的主要疾病之一。上转换纳米颗粒（UCNPs）是有望检测和治疗癌症的新型纳米材料之一。一步水热法可以合成具有可控的理化性质和低生物毒性的UCNPs。在这项工作中，通过一步水热法合成了油酸（OA）和聚乙二醇（PEG）修饰的NaGdF ₄ / GdF ₃：Yb，Er UCNP。通过X射线衍射（XRD），透射电子显微镜（TEM），X射线光电子能谱（XPS），傅里叶变换红外光谱（FTIR）以及超导量子干涉仪（SQUID）对制备的UCNP进行了表征。 ）。修饰的NaGdF ₄ / GdF ₃的细胞毒性：Yb，Er UCNPs被评估。结果表明，OA修饰的UCNPs为六角形的NaGdF ₄相，而PEG修饰的UCNPs为正交晶形的GdF ₃相。OA-修饰的和PEG-修饰的UCNP的粒径分别为约15nm和约30nm。修饰的UCNP具有良好的磁性能和强的上转换发光性能（UCL），其中PEG修饰的UCNP的性能比OA修饰的UCNP的性能稍好。当纳米颗粒的浓度从62.5增加到500μg/ mL时，OA-NaGdF ₄：Yb，Er表现出一定的细胞毒性，并表现出剂量效应关系。但是，PEG-GdF ₃：Yb，Er没有显示出明显的细胞毒性。因此，PEG修饰的UCNPs可能更适用于肿瘤学领域。