在SABRE-SHEATH的多维pH-温度映射中13C [1-13C]Pyruvate的超极化
Isaiah Adelabu1, Joseph Gyesi1, Md Raduanul H Chowdhury1
1Department of Chemistry, Integrative Biosciences (Ibio), Wayne State University, Karmanos Cancer Institute (KCI), Detroit, Michigan 48202, United States.
The journal of physical chemistry. B
|November 22, 2025
概括
在SHield中通过可逆交换进行信号放大,使对齐转移到异质核 (SABRE-SHEATH) 成为一种更快,更便宜的方法来产生超极化[1-13C]pyruvate. 在pH值6.5-7.7和6°C的最佳条件下,在代谢成像中产生高极化.
科学领域:
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
- 医疗成像医学成像
- 化学物理 化学物理
背景情况:
- 超极化[1-13C]酸盐是体内代谢流量成像的关键探针,目前在众多临床试验中使用.
- 通过溶解动态核极化 (d-DNP) 进行传统的生产是昂贵的 (>200万美元) 和耗时的 (1小时).
- 通过Shield中的可逆交换进行信号放大,使对齐转移到异质核 (SABRE-SHEATH) 成为一个有希望的,具有成本效益的 (低于2000美元) 替代方案,可实现快速 (1分钟) 的生产.
研究的目的:
- 为了研究pH值和温度对[1-13C]pyruvate的SABRE-SHEATH高极化的影响.
- 为了优化SABRE-SHEATH条件,增强超极化[1-13C]pyruvate生产.为了优化SABRE-SHEATH条件,增强超极化[1-13C]pyruvate生产.
- 了解影响pyruvate交换和13C放松动态的潜在机制.
主要方法:
- 利用SABRE-SHEATH技术使用Ir-IMes催化剂进行超极化.
- 在催化剂上研究了对和[1-13C]pyruvate的同时化学交换.
- 分析了结合体 (DMSO) 的作用和酸盐 (赤道) 的结合位置,以实现高效的极化转移.
主要成果:
- 在6.5-7.7的甲醇pH值和6°C的温度下确定了最佳的超极化条件.
- 在催化剂结合的酸中达到高13C极化水平,超过25%.
- 与0.4μT的相关C放松动态与观察到的极化水平,支持这些发现.
结论:
- 温度和pH值显著且互补地调节了SABRE-SHEATH超极化过程.
- 优化的SABRE-SHEATH方法提供了一个高效的生产超极化[1-13C]pyruvate的途径.
- 这项工作加深了对SABRE-SHEATH的理解,并为改善分子成像中的超极化技术铺平了道路.
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