Abstract Folic acid and D-gluconic acid-capped gadolinium oxide nanorods and nanocuboids were synthesized via co-precipitation method. Comparative study of relaxivity factor on the role of capping and morphology for enhancing contrast ability for T 1 and T 2 magnetic resonance imaging (MRI) was investigated. The obtained r 2 / r 1 ratio for folic acid and D-gluconic acid-capped gadolinium oxide nanorods and nanocuboids was 1.5 and 1.3, respectively. The nanocrystals were characterized and presented with properties such as good dispersity and stability required for standard contrast agent used in MRI. The characterization and the analysis of capping agent for nanocrystals suggest the preferable use of carbohydrate moieties with higher number of hydroxyl functional group reacted with urea and hydrogen peroxide for desired morphology and anisotropic growth. Thermogravimetric–differential thermal analysis (TG–DTA) illustrated the amount of capping, transition temperature from Gd(OH) 3 to GdOOH and crystallization temperature from GdOOH to Gd 2 O 3 . These nanocrystals would be significant for other biomedical applications such as drug delivery when equipped with well-functionalized drug molecules. Graphic abstract Synergistic effects and mechanism of urea, hydrogen peroxide and capping agent for growth and morphology.

中文翻译：

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用于生物成像的表面工程氧化钆纳米棒和纳米长方体

摘要 采用共沉淀法合成了叶酸和D-葡萄糖酸封端的氧化钆纳米棒和纳米长方体。研究了弛豫因子对增强 T 1 和 T 2 磁共振成像 (MRI) 对比能力的作用和形态作用的比较研究。获得的叶酸和 D-葡萄糖酸封端的氧化钆纳米棒和纳米立方体的 r 2 / r 1 比分别为 1.5 和 1.3。纳米晶体被表征并呈现出诸如用于 MRI 的标准造影剂所需的良好分散性和稳定性等特性。纳米晶体封端剂的表征和分析表明，优选使用具有更多羟基官能团的碳水化合物部分与尿素和过氧化氢反应以获得所需的形态和各向异性生长。热重-差热分析 (TG-DTA) 说明了封端量、从 Gd(OH) 3 到 GdOOH 的转变温度以及从 GdOOH 到 Gd 2 O 3 的结晶温度。当配备功能良好的药物分子时，这些纳米晶体对于其他生物医学应用（例如药物输送）具有重要意义。图形摘要尿素、过氧化氢和封端剂对生长和形态的协同作用和机制。从 Gd(OH) 3 到 GdOOH 的转变温度和从 GdOOH 到 Gd 2 O 3 的结晶温度。当配备功能良好的药物分子时，这些纳米晶体对于其他生物医学应用（例如药物输送）具有重要意义。图形摘要尿素、过氧化氢和封端剂对生长和形态的协同作用和机制。从 Gd(OH) 3 到 GdOOH 的转变温度和从 GdOOH 到 Gd 2 O 3 的结晶温度。当配备功能良好的药物分子时，这些纳米晶体对于其他生物医学应用（例如药物输送）具有重要意义。图形摘要尿素、过氧化氢和封端剂对生长和形态的协同作用和机制。