DFTMP是一种NMR试剂,用于评估生物样本的近中性pH值
Michael D Reily1, Lora C Robosky, Matthew L Manning
1Pfizer Global Research and Development, 2800 Plymouth Road, Ann Arbor, Michigan 48105, USA. michael.reily@pfizer.com
Journal of the American Chemical Society
|September 21, 2006
概括
一种新型试剂,二二甲基基酸 (DFTMP),可以使用NMR在生物流体中准确地在现场测量pH值. 这种多核指标比现有方法在复杂样本中准确测定pH值具有优势.
科学领域:
- 分析化学 分析化学
- 生物化学 生物化学
- 核磁共振 (NMR) 光谱学 核磁共振 (NMR) 光谱学
背景情况:
- 准确的in situ pH测定对于理解生物过程至关重要.
- 现有的pH指标可能会干扰生物样品或NMR光谱.
- 对于复杂的生物流体,需要一个可靠的,不干扰的pH指标.
研究的目的:
- 引入二三甲基西兰酸 (DFTMP) 作为一种新的NMR化学转移标准和pH指标.
- 为了证明DFTMP在复杂生物流体中的in situ pH测定中的实用性.
- 为了突出DFTMP与之前描述的pH敏感元件的优势.
主要方法:
- 二三甲基西兰酸 (DFTMP) 的合成和表征.
- 对DFTMP的NMR信号的pH依赖性的评估.
- 应用DFTMP用于在水溶液和生物流体中的in situ pH测量,使用NMR光谱学.
主要成果:
- DFTMP表现出依赖pH的NMR化学变化.
- 准确的现场pH测定,RMSE为0.02的pH单位,pH范围为5到8.
- DFTMP没有金属结合亲和力,对内源光谱区域的干扰最小.
结论:
- 在复杂的生物系统中,DFTMP作为一种有价值的试剂,用于准确地在现场确定pH值.
- 它的多核能力 (19F,1H,31) 和无干扰性使其优于现有方法.
- DFTMP广泛适用于需要精确的实时pH监测的NMR实验.
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