Abstract This work was primarily focused on the synthesis, characterization and biomedical applications of cobalt ferrite (CoFe2O4) nanoparticles, which were synthesized by a facile solvothermal method using an amino acid of Leucine (Leu) as the surface coating agents. The morphology, structure and properties of the as-synthesized uncoated and Leu-coated CoFe2O4 nanoparticles were characterized in detail by means of XRD, SEM, TEM, DLS, FTIR, XPS, TGA and SQUID. More importantly, it was found that the Leu-coated CoFe2O4 nanoparticles can be used as the efficient drug delivery with a drug loading capacity of 0.32 mg/mg for doxorubicin hydrochloride (DOX), and the loaded DOX demonstrated a sustained and progressive release manner. The in vitro cytotoxicity studies towards the HeLa cells were carried out, and the results indicated that the Leu-coated CoFe2O4 nanoparticles exhibited a relatively high cell viability compared with that of bare CoFe2O4 nanoparticles and the DOX loaded Leu-coated CoFe2O4 nanoparticles presented an obvious cytotoxic effect on HeLa cells.

中文翻译：

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亮氨酸涂层铁氧体钴纳米粒子：药物递送的合成、表征和潜在的生物医学应用

摘要 这项工作主要集中在铁氧体钴 (CoFe2O4) 纳米粒子的合成、表征和生物医学应用上，该纳米粒子是通过简便的溶剂热法合成的，使用亮氨酸 (Leu) 氨基酸作为表面涂层剂。通过 XRD、SEM、TEM、DLS、FTIR、XPS、TGA 和 SQUID 对合成的未涂覆和 Leu 涂覆的 CoFe2O4 纳米粒子的形貌、结构和性质进行了详细表征。更重要的是，发现 Leu 包覆的 CoFe2O4 纳米颗粒可作为有效的药物递送，对盐酸多柔比星 (DOX) 的载药量为 0.32 mg/mg，并且负载的 DOX 表现出持续和渐进的释放方式。对 HeLa 细胞进行了体外细胞毒性研究，