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用FTIR测定氧基酸的摩尔替代程度

Fang Liu¹, Yinchun Liu¹, Youli Guo²

¹State Key Laboratory Base of Eco-chemical Engineering, College of Chemical Engineering, Qingdao University of Science and Technology, No.53 Zhengzhou Road, Qingdao 266042, China.

Carbohydrate polymers

|June 1, 2024

概括

一种新的富里埃变换红外线 (FTIR) 方法准确地确定氧基 (HPCS) 分子替代 (MS). 这种经过验证的技术为HPCS分析提供了核磁共振 (NMR) 的强大替代方案.

科学领域:

分析化学分析化学
聚合物科学聚合物科学
生物材料科学生物材料科学

背景情况:

氧基 (HPCS) 是一种具有可调节性质的多功能基衍生物.
准确地确定摩尔置换 (MS) 的程度对于控制HPCS特征至关重要.
现有的MS确定方法可能在简单性或适用性方面存在局限性.

研究的目的:

开发和验证一种新的富里埃变换红外 (FTIR) 方法,用于量化基酸 (HPCS) 的摩尔替代 (MS).
建立FTIR作为一种可靠和可访问的替代方案,用于核磁共振 (H NMR) 确定MS.
通过FTIR确定最佳的光谱区域和整合方法,以准确地使用MS量化.

主要方法:

福里埃变换红外光谱法 (FTIR) 用于分析20个具有不同程度乙化度的HPCS样品.
对集成方法和光谱带进行了广泛的选,以将FTIR数据与参考H NMR测量相关联.
方法验证包括在定义的MS范围内评估线性,恢复和精度 (RSD).

主要成果:

在H NMR衍生的MS值和FTIR光谱比率之间,使用2970厘米的频带面积作为探针,实现了线性相关性 (R^2>0.98).
在3440厘米^-1和1415厘米^-1的最佳参考波段,在0.17-1.92范围内的MS确定产生了高可靠性 (R^2>0.99).
2875厘米-1的波段对微量水分的敏感性降低,提高了测试的稳定性.
方法验证显示了高准确度 (平均恢复98.9±2.8%) 和精度 (RSD<10%).

结论:

成功开发并验证了一种新,简单,强大,准确和精确的FTIR方法,用于确定HPCS的MS.
这种FTIR方法为HNMR提供了可靠的替代方案,特别是用于例行分析.
强调了该方法对不溶性HPCS衍生物和其他基化多糖的潜在可扩展性.

关键词:

分析分析分析基托桑是一种酸盐.美国的FTIR是FTIR.氧烯是一种氧烯.这是一个完整的整体.替代替代替代替代替代

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