Gas-phase proton-transfer chemistry coupled with TOF mass spectrometry and ion mobility-MS for the facile analysis of poly(ethylene glycols) and PEGylated polypeptide conjugates
Gas-phase proton-transfer chemistry coupled with TOF mass spectrometry and ion mobility-MS for the facile analysis of poly(ethylene glycols) and PEGylated polypeptide conjugates
复制标题
DOI：
10.1021/ac7020163
复制
发表时间：
2008-04-01
影响因子：
7.4
通讯作者：
Schnier, Paul D.
中科院分区：
文献类型：
--
作者：
Bagal, Dhanashri;Zhang, Heidi;Schnier, Paul D.
气相离子/分子化学与离子迁移率分离和飞行时间质谱仪相结合，能够表征大分子聚乙二醇S(PEGS)和聚乙二醇化分子(>；40 kDa)。提出了一种在商用TOF质谱仪的高压源区与气相超强碱反应来操纵电喷雾电离(ESI)产生的大离子的电荷态的简便方法。电荷剥离减少了通常在高相对分子质量多分散聚乙二醇化分子的ESI质谱图中观察到的光谱拥堵。根据这些数据，可以准确地确定合成聚合物和聚乙二醇化蛋白质的平均分子量和分子量分布。聚乙二醇化的粒细胞集落刺激因子(rh-GCSF，40 726.2 Da)的平均相对分子质量与理论值吻合较好，异相聚乙二醇化蛋白的氧化形式的光谱容易观察到16Da的质量位移。离子迁移率分离可以分离不同链长的钉子；当与电荷剥离离子/分子反应相结合时，离子迁移率质谱学(IMMS)在表征大分子的聚乙二醇化程度方面具有几个分析优势，包括增强的动态范围、更高的灵敏度和特异度。用气相离子/分子化学结合离子迁移率质谱仪可以很容易地观察到聚乙二醇化多肽制剂中的低丰度游离聚乙二醇酯，并且可以准确地定量。
Gas-phase ion/molecule chemistry has been combined with ion mobility separation and time-of-flight mass spectrometry to enable the characterization of large poly(ethylene glycol)s (PEGs) and PEGylated molecules (>40 kDa). A facile method is presented in which gas-phase superbases are reacted in the high-pressure source region of commercial TOF mass spectrometers to manipulate the charge states of large ions generated by electrospray ionization (ESI). Charge stripping decreases the spectral congestion typically observed in ESI mass spectra of high molecular weight polydisperse PEGylated molecules. From these data, accurate average molecular weights and molecular weight distributions for synthetic polymers and PEGylated proteins are determined. The average MW measured for PEGylated Granulocyte colony-stimulating factor (rh-GCSF, 40 726.2 Da) is in good agreement with the theoretical value, and a 16 Da mass shift is easily observed in the spectrum of an oxidized form of the heterogeneous PEGylated protein. Ion mobility separations can fractionate PEGs of different chain length; when coupled with charge stripping ion/molecule reactions, ion mobility mass spectrometry (IMMS) offers several analytical advantages over mass spectrometry alone for the characterization of large PEGylated molecules including enhanced dynamic range, increased sensitivity, and specificity. Low abundance free PEG in a PEGylated peptide preparation, which is not directly detectable by mass spectrometry, can be easily observed and accurately quantified with gas-phase ion/molecule chemistry combined with ion mobility mass spectrometry.