[6]uril 超极化化学交换和转移脉冲序列参数优化和可检测性极限评估在3.0T
Vira Grynko1,2, Yurii Shepelytskyi1,3, Viktoriia Batarchuk1,3
1Thunder Bay Regional Health Research Institute, 1040 Oliver Rd, Thunder Bay, ON P7B 7A5, Canada.
Chemphyschem : a European journal of chemical physics and physical chemistry
|September 15, 2023
概括
优化高极化 (HP) 的XeMRI对比剂,如Cucurbit[6]uril (CB6),对于个性化医学至关重要. 这项研究优化了脉冲序列,实现了30%的血液枯竭,使红细胞中的分子成像成为可能.
科学领域:
- 医疗成像医学成像
- 生物物理学的生物物理.
- 纳米技术 纳米技术
背景情况:
- 分子成像是个性化医学的关键,需要有效的对比剂.
- 超极化XeMRI与化学交换和转移 (HyperCEST) 提供了高效率.
- 黄瓜[6]uril (CB6) 显示作为一个HyperCEST代理的承诺,但需要临床优化.
研究的目的:
- 在临床环境中优化MRI脉冲序列参数用于CB6.
- 评估不同脱极化脉冲形状的性能.
- 使用优化序列,确定血液中CB6的检测极限.
主要方法:
- 在酸盐缓冲盐水 (PBS) 和牛血中对CB6的优化MRI脉冲序列参数.
- 测试了四种脱极化脉冲形状:正弦形,三叶形 (3LS),矩形和过波形.
- 在临床3.0TMRI扫描仪中评估CB6检测极限.
主要成果:
- 三叶片sinc (3LS) 脉冲形状产生了最佳性能,在25μM CB6 PBS溶液中达到24%的耗尽.
- 在化牛血中,CB6的检测极限为100μM,HyperCEST的减弱率为30%±9%.
- 第一次观察到Xe HyperCEST效应在红细胞中,与血相当.
结论:
- 优化的3LS脉冲序列在临床MRI扫描仪中显著提高CB6性能.
- 在血液中达到临床相关的CB6检测极限,为体内应用铺平了道路.
- 证明了观察红细胞内Xe HyperCEST效应的可行性,扩大了其分子成像潜力.
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