Determination of collisional cross sections (CCS) by travelling wave ion mobility mass spectrometry (TWIM-MS) requires calibration against standards for which the CCS has been measured previously by drift tube ion mobility mass spectrometry (DTIM-MS). The different extents of collisional activation in TWIM-MS and DTIM-MS can give rise to discrepancies in the CCS of calibrants across the two platforms. Furthermore, the conditions required to ionize and transmit large, folded proteins and assemblies may variably affect the structure of the calibrants and analytes. Stable hetero-oligomeric phospholipase A₂ (PDx) and its subunits were characterized as calibrants for TWIM-MS. Conditions for acquisition of native-like TWIM (Synapt G1 HDMS) and DTIM (Agilent 6560 IM-Q-TOF) mass spectra were optimized to ensure the spectra exhibited similar charge state distributions. CCS measurements (DTIM-MS) for ubiquitin, cytochrome c, holo-myoglobin, serum albumin and glutamate dehydrogenase were in good agreement with other recent results determined using this and other DTIM-MS instruments. PDx and its β and γ subunits were stable across a wide range of cone and trap voltages in TWIM-MS and were stable in the presence of organic solvents. The CCS of PDx and its subunits were determined by DTIM-MS and were used as calibrants in determination of CCS of native-like cytochrome c, holo-myoglobin, carbonic anhydrase, serum albumin and haemoglobin in TWIM-MS. The CCS values were in good agreement with those measured by DTIM-MS where available. These experiments demonstrate conditions for analysis of native-like proteins using a commercially available DTIM-MS instrument, characterize robust calibrants for TWIM-MS, and present CCS values determined by DTIM-MS and TWIM-MS for native proteins to add to the current literature database.

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通过行波离子迁移率质谱法（TWIM-MS）确定碰撞截面（CCS）需要根据先前已通过漂移管离子迁移率质谱法（DTIM-MS）测量CCS的标准进行校准。TWIM-MS和DTIM-MS中碰撞激活程度的不同会导致跨两个平台的校准物的CCS差异。此外，电离和传输大的折叠蛋白和装配体所需的条件可能会不同地影响校准物和分析物的结构。稳定的异寡聚磷脂酶A ₂（PDx）及其亚基被表征为TWIM-MS的校准物。优化了获取类似天然TWIM（Synapt G1 HDMS）和DTIM（Agilent 6560 IM-Q-TOF）质谱的条件，以确保光谱显示出相似的电荷状态分布。泛素，细胞色素c，全肌红蛋白，血清白蛋白和谷氨酸脱氢酶的CCS测量（DTIM-MS）与使用本仪器和其他DTIM-MS仪器测定的其他近期结果非常吻合。在TWIM-MS中，PDx及其β和γ亚基在很宽的锥电压和阱电压范围内都是稳定的，并且在有机溶剂存在下也是稳定的。用DTIM-MS测定PDx及其亚基的CCS，并将其用作测定天然样细胞色素c CCS的校准物，TWIM-MS中的全血肌红蛋白，碳酸酐酶，血清白蛋白和血红蛋白。CCS值与DTIM-MS测得的值一致。这些实验证明了使用市售DTIM-MS仪器分析天然样蛋白的条件，表征了TWIM-MS的鲁棒校准物，并提供了由DTIM-MS和TWIM-MS测定的天然蛋白的CCS值，以添加到当前文献中。数据库。

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