牙膏中的锡的结构特征通过动态核极化增强Sn固态NMR光谱学119
Rick W Dorn1,2, Scott L Carnahan1,2, Chi-Yuan Cheng3
1US Department of Energy Ames National Laboratory, Ames, IA, 50011, USA.
Nature communications
|November 17, 2023
概括
使用119Sn固态NMR的动态核极化 (DNP) 成功确定了牙膏中的锡物种化. 这种方法显示,大多数商业牙膏主要含有活性Sn (II) 形式,其中一种含有较高的Sn (IV) 含量.
科学领域:
- 材料科学 材料科学 材料科学
- 分析化学 分析化学
- 生物材料是一种生物材料.
背景情况:
- 化物 (SnF2) 是牙膏的关键成分,因其化物和与Sn (II) 离子相关的抗菌特性而受到重视.
- 由于度低,以及产品的复杂基质,分析牙膏中的锡物种化是很困难的.
- 了解锡的氧化状态对于优化牙膏的有效性和稳定性至关重要.
研究的目的:
- 开发和应用一种敏感的方法来确定商业牙膏中的锡特异性.
- 为了研究各种牙膏配方中存在的锡的氧化状态.
- 要量化所选牙膏产品中Sn (II) 和Sn (IV) 的相对含量.
主要方法:
- 利用动态核极化 (DNP) 来增强119Sn固态核磁共振 (NMR) 光谱中的信号检测.
- 采用了119Sn神奇转角 (MAT) 2D NMR和1H →119Sn交叉极化NMR技术.
- 分析了119Sn化学转移异构性 (CSA) 和19F异构性化学转移作为锡氧化状态的指标.
主要成果:
- 用DNP增强的119SnNMR成功地根据它们独特的化学转移张量参数解决了Sn (II) 和Sn (IV) 物种.
- 对四种商业牙膏的分析表明,其中三种牙膏主要含有Sn (≥80%).
- 一种牙膏配方被发现含有Sn (IV) 的比例明显高于Sn (II).
结论:
- 用DNP增强的119Sn固态NMR是一种强大的技术,用于探测牙膏等复杂的半固态矩阵中的锡物种化.
- 该研究提供了关于商业口腔护理产品中存在的实际锡氧化状态的见解.
- 这些发现突出了牙膏配方的潜在差异,以及对活性锡物种进行质量控制的需要.
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