A range of poly ethoxy ethyl glycinamide (PEE−G) dendron scaffolds with gadolinium (III) complexes attached were synthesized with a focus on product purity and high Gd(III) loading. The nuclear magnetic resonance relaxivity of these products was measured and compared with commercially available low‐molecular‐weight magnetic resonance imaging contrast agents. Over twice the relaxivity based on Gd(III) concentration, and up to 20‐fold increase in relaxivity were observed based on molecular concentration. Relaxivity properties were observed to increase with both increasing molecular weight and number of Gd(III) complexes attached, however a plateau was reached for molecular weight increase. T₁ and T₂ relaxivity properties were also investigated at two different magnetic fields. Transverse relaxivity is unaffected by magnetic field strength whereas increase in longitudinal relaxivity was not as pronounced at the higher field.

中文翻译：

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Poly复合物连接到聚乙氧基乙酰胺（PEE-G）树突上：磁共振成像造影剂具有增加的弛豫性。

合成了一系列带有g（III）配合物的聚乙氧基乙基甘氨酰胺（PEE-G）树突支架，重点是产品纯度和高Gd（III）负载量。测量了这些产品的核磁共振弛豫性，并与市售的低分子量磁共振成像造影剂进行了比较。基于Gd（III）浓度的弛豫率是原来的两倍多，而基于分子浓度的弛豫率则提高了20倍。观察到弛豫性随分子量和附着的Gd（III）配合物数量的增加而增加，但是分子量增加达到了平稳状态。T ₁和T ₂还研究了在两个不同磁场下的弛豫特性。横向弛豫率不受磁场强度的影响，而纵向弛豫率的增加在较高磁场下并不明显。