15NNMR信号放大通过可逆交换的[15N3]奥尼达抗生素
Anna P Yi1,2, Nikita V Chukanov1, Mohammad S H Kabir3
1International Tomography Center SB RAS, 3A Institutskaya St., Novosibirsk 630090, Russia.
The journal of physical chemistry. B
|October 27, 2025
概括
通过屏蔽中可逆交换的信号放大使对齐转移到异质核 (SABRE-SHEATH) 的超极化增强NNMR对ornidazole的敏感性. 这项技术有助于使用磁共振成像对缺氧瘤进行可视化.
科学领域:
- 磁共振光谱学和成像技术
- 超极化技术 超极化技术
- 核磁共振 (NMR) 是一种核磁共振技术.
背景情况:
- 超极化极大地提高了MRI和MRS的灵敏度.
- 尼特罗伊米达抗生素对可视化缺氧瘤有希望,因为它们在无氧条件下减少.
- 通过屏蔽中的可逆交换进行信号放大,使对齐转移到异质核 (SABRE-SHEATH) 是C和N核的有效超极化方法.
研究的目的:
- 为了研究15N SABRE-SHEATH的高极化,在ornidazole.
- 为了优化实验条件以增强N极化.
- 评估15NNMR在低氧环境中检测鸟醇及其还原产品的潜力.
主要方法:
- 系统研究15N SABRE-SHEATH超极化对于自然丰富性和15N3标记的ornidazole.
- 极化转移磁场,温度,气压力和流速的优化.
- 密度函数理论 (DFT) 计算了15N个化学转移.
主要成果:
- 获得的平均N极化水平为9.3%的自然丰富性ornidazole和5.3%的N极化水平.ornidazole.
- 获得了7.4分钟的T1极化衰变时间,用于1.4 T的[15NO2组的[15N3]ornidazole.
- 经过超极化后20分钟的NNMR信号检测.
结论:
- N SABRE-SHEATH的超极化对ornidazole来说是有效的.
- 优化条件产生显著的极化水平和长时间的信号持久性.
- 15NNMR可以区分奥尔尼达及其低毒性降解产物,有助于瘤可视化.
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