Baxter Healthcare, WG3-3S, 25212W, Illinois Rte. 120, Round Lake, IL 60073, USA.
Anal Bioanal Chem. 2011 Jan;399(2):651-62. doi: 10.1007/s00216-010-4262-y. Epub 2010 Oct 15.
This article addresses the identification and quantification of the chemical species resulting in resonances at 2.17 and 2.25 ppm in the (1)H nuclear magnetic resonance (NMR) spectrum of pharmaceutical-grade heparin sodium. The NMR signals in question were first confirmed to arise from chemical moieties covalently attached to the heparin molecule through NMR diffusion experiments as well as chemical treatment of heparin active pharmaceutical ingredient (API) containing the resonances. The material responsible for the extra NMR signals was then demonstrated by NMR spiking studies to be something other than oversulfated chondroitin sulfate and was finally identified as an O-acetylation product of heparin through (13)C labeling experiments with subsequent NMR analysis. The extent of O-acetylation was quantified using three orthogonal techniques: (1)H NMR, ion chromatography, and headspace gas chromatography/mass spectrometry. The results of this work showed good agreement between the three quantitative methods developed to analyze the signals in the United States Pharmacopeia-specified region of 2.12-3.00 ppm for heparin API.
本文旨在确定和量化制药级肝素钠的 (1)H 核磁共振 (NMR) 图谱中在 2.17 和 2.25 ppm 处产生共振的化学物质。通过 NMR 扩散实验以及对含有共振的肝素活性药物成分 (API) 进行化学处理，首先确认了所讨论的 NMR 信号来自通过共价键连接到肝素分子上的化学基团。通过 NMR 加标研究，进一步证明了负责额外 NMR 信号的物质不是过度硫酸化的软骨素硫酸盐，最终通过 (13)C 标记实验和随后的 NMR 分析，将其鉴定为肝素的 O-乙酰化产物。通过三种正交技术：（1）H NMR、离子色谱和顶空气相色谱/质谱法，对 O-乙酰化程度进行了定量。这项工作的结果表明，三种定量方法在分析美国药典规定的肝素 API 2.12-3.00 ppm 区域内的信号时具有良好的一致性。
