高分子量未知化合物的精确质量差异从已解决的同位素分布:寡核酸杂质
1Ionis Pharmaceuticals Inc, Analytical Development & Quality Control, 2855, Gazelle Ct., Carlsbad, California 92010-6670, United States.
Analytical chemistry
|November 27, 2025
概括
使用质谱测量来确定高分子量 (HMW) 化合物的公式具有挑战性. 新的方法可以准确计算同位素分布之间的质量差异 (ΔM),简化了像寡核酸等复杂分子的公式识别.
科学领域:
- 分析化学 分析化学
- 生物化学 生化学
- 计算化学计算化学
背景情况:
- 高分辨率质谱 (HRMS) 对于识别未知的高分子量 (HMW) 化合物至关重要.
- 对于HMW化合物,如寡核酸,准确的配方确定是复杂的,因为有许多可能性.
- 质量差 (ΔM) 方法显著减少了候选公式,但在精确的ΔM计算方面面临挑战.
研究的目的:
- 解决HMW化合物的同位素分布之间的质量差异 (ΔM) 的准确确定方面的挑战.
- 开发可靠的 ΔM 计算方法,克服使用最丰富质量 (MAbM) 和单同位素质量的局限性.
- 为了提高HMW物种的HRMS分析中的配方候选减少的可靠性.
主要方法:
- 开发了两种新的,相当的方法来准确地确定同位素分布之间的ΔM.
- 利用光滑的同位素分布来估计初始的近似 ΔM.
- 用同位素对的质量中心 (具有实证间隔) 和组合质量中心 (通用) 进行精确的 ΔM 计算.
主要成果:
- 两种开发的方法都实现了等效的质量准确度,用于 ΔM 确定.
- 组合方法在简单性和普遍性方面表现出优势,消除了对经验质量间隔的需求.
- 成功解决了MAbM和单同位素峰值选择中的实验不确定性.
结论:
- 开发的方法为HMW化合物提供了准确的质量差异 (ΔM),提高了公式的确定.
- 组合方法为HRMS中的ΔM计算提供了更普遍和更简单的解决方案.
- 这些进步有助于更可靠地识别复杂的生物分子,如寡核酸.
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