F. M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland, ‡Department of Radiology, §Department of Chemical & Biomolecular Engineering, and ∥Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21205, United States.
Anal Chem. 2017 Jul 18;89(14):7758-7764. doi: 10.1021/acs.analchem.7b01763. Epub 2017 Jul 5.
The development of new analytical methods to accurately quantify hydrogen peroxide is of great interest. In the current study, we developed a new magnetic resonance (MR) method for noninvasively quantifying hydrogen peroxide (HO) in aqueous solutions based on chemical exchange saturation transfer (CEST), an emerging MRI contrast mechanism. Our method can detect HO by its specific CEST signal at ∼6.2 ppm downfield from water resonance, with more than 1000 times signal amplification compared to the direct NMR detection. To improve the accuracy of quantification, we comprehensively investigated the effects of sample properties on CEST detection, including pH, temperature, and relaxation times. To accelerate the NMR measurement, we implemented an ultrafast Z-spectroscopic (UFZ) CEST method to boost the acquisition speed to 2 s per CEST spectrum. To accurately quantify HO in unknown samples, we also implemented a standard addition method, which eliminated the need for predetermined calibration curves. Our results clearly demonstrate that the presented CEST-based technique is a simple, noninvasive, quick, and accurate method for quantifying HO in aqueous solutions.
开发能够准确量化过氧化氢的新分析方法具有重要意义。在本研究中，我们基于新兴的磁共振（MR）对比机制——化学交换饱和转移（CEST），开发了一种新的非侵入性定量检测水溶液中过氧化氢（HO）的磁共振方法。我们的方法可以通过水共振下约 6.2ppm 的 HO 特有的 CEST 信号来检测 HO，与直接 NMR 检测相比，信号放大超过 1000 倍。为了提高定量的准确性，我们全面研究了样品性质对 CEST 检测的影响，包括 pH 值、温度和弛豫时间。为了加速 NMR 测量，我们实现了超快 Z 谱（UFZ）CEST 方法，将采集速度提高到每 CEST 谱 2 秒。为了准确量化未知样品中的 HO，我们还实现了标准添加法，消除了对预定校准曲线的需求。我们的结果清楚地表明，所提出的基于 CEST 的技术是一种简单、非侵入性、快速和准确的定量检测水溶液中 HO 的方法。
