稳定和惰性的基和pH响应的对比剂
Richárd Botár1, Enikő Molnár1, György Trencsényi2
1Department of Physical Chemistry , University of Debrecen , H-4032 Debrecen , Hungary.
Journal of the American Chemical Society
|January 14, 2020
概括
研究人员使用PC2A-EA连接体开发了一种新的 (II) 复合体. 这种pH敏感的对比剂显示出在生物学相关的pH范围内的MRI应用的潜力.
科学领域:
- 无机化学 无机化学
- 材料科学 材料科学 材料科学
- 生物医学成像技术 生物医学成像技术
背景情况:
- 基于 (II) 离子开发用于磁共振成像 (MRI) 的智能/智能对比剂是具有挑战性的,因为典型复合物的不稳定性.
- 现有的聚氨酸碳酸盐类型连接体经常与Mn2形成不稳定的复合体,从而限制了它们的实用性.
研究的目的:
- 举报了环境pH值变化激活的Mn(II) 复合物的第一个例子.
- 为了研究一种新型的Mn (II) 复合物与特定的连接体的稳定性和运动惰性.
- 为了评估复合物的pH依赖性放松性,用于潜在的MRI应用.
主要方法:
- 合成和表征一个Mn (II) 复合物与PC2A-EA联体.
- 确定热力学稳定性 (log K_MnL) 和运动惰性.
- 测量水交换率的方法.
- 在生物相关的pH范围 (6-8) 中评估pH依赖的协调和放松性.
主要成果:
- 该PC2A-EA连接体形成了一个热力学稳定 (log K_MnL = 19.01,pMn = 9.27) 和动态惰性的Mn{\displaystyle Mn}II) 复合体.
- 该综合体具有相对较慢的水交换率 ((4.0 ± 0.2) × 10^7 s^-1).
- 在6-8的pH范围内,乙胺部分的pH依赖协调 (log K_MnL^H = 6.88) 会导致pH敏感的放松性.
结论:
- 已经合成了一种具有pH可激活性质的新型,稳定和动态惰性Mn{\displaystyle Mn{\text{II}} } 复合物.
- 该复合体在生物学相关的pH范围内显示出pH敏感的放松性,表明其作为智能MRI对比剂的潜力.
- 这些发现为开发有针对性和响应性的MRI对比剂开辟了新的途径.
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