Ultrasmall silica nanoparticles (NPs), having hydrodynamic diameters under 10 nm are promising inorganic platforms for imaging and therapeutic applications in medicine. Herein is described a new way for synthesizing such kind of NPs in a one-pot scalable protocol. These NPs bear DOTA (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) ligands on their surface that can chelate different metals suitable for a wide variety of biomedical applications. By varying the ratio of the precursors, the hydrodynamic diameters of the particles can be controlled over the range of 3 to 15 nm. The resulting NPs have been characterized extensively by complementary techniques like dynamic light scattering (DLS), high performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), mass spectrometry (MS), phosphorescence titration, photophysical measurements, relaxometry and elemental analysis to elucidate their structures. Chelation of gadolinium (Gd) allowed its use as an effective intravenous contrast agent in MRI and was illustrated in mice bearing colorectal CT26 tumors. The new particle appears to sufficiently accumulate in the tumors and efficiently clear out of animal bodies through kidneys. This new synthesis is an original, time/material-saving and very flexible process that can be applied for creating versatile ultrasmall multifunctional nanomedicines.

中文翻译：

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一锅直接合成多功能超小型杂化二氧化硅纳米粒子†

具有小于10 nm的流体动力学直径的超小二氧化硅纳米粒子（NPs）是用于医学成像和治疗应用的有前途的无机平台。这里描述了一种在单锅可扩展协议中合成这种NP的新方法。这些NP在其表面带有DOTA（1,4,7,10-四氮杂环十二烷-1,4,7,10-四乙酸）配体，可以螯合适用于多种生物医学应用的不同金属。通过改变前体的比例，可以将颗粒的流体动力学直径控制在3至15nm的范围内。产生的NP已通过互补技术（例如动态光散射（DLS），高效液相色谱（HPLC），核磁共振（NMR），质谱（MS），磷光滴定，光物理测量，弛豫法和元素分析以阐明其结构。（Gd）的螯合使其可以在MRI中用作有效的静脉造影剂，并在患有结直肠CT26肿瘤的小鼠中得到了说明。新颗粒似乎在肿瘤中充分积聚，并通过肾脏有效清除出动物体。这种新的合成方法是一种原始的，节省时间/材料且非常灵活的方法，可用于创建通用的超小型多功能纳米药物。新颗粒似乎在肿瘤中充分积聚，并通过肾脏有效清除出动物体。这种新的合成方法是一种原始的，节省时间/材料且非常灵活的方法，可用于创建通用的超小型多功能纳米药物。新颗粒似乎在肿瘤中充分积聚，并通过肾脏有效清除出动物体。这种新的合成方法是一种原始的，节省时间/材料且非常灵活的方法，可用于创建通用的超小型多功能纳米药物。