离子迁移(ion mobility)是一种在分子离子化后,非溶液环境下的分离技术。与依靠离子质量与电荷比进行分离的质谱技术不同,离子迁移是根据离子形状与电荷比实现分离的。因此,离子迁移技术可以实现对质量相同而形状不同的离子分离,其与质谱技术联用可为研究者提供更加丰富的结构信息。最新发展的行波离子迁移技术大大提高了灵敏度和分离速度,适用于研究天然浓度条件下的蛋白质,其在蛋白质单体折叠与去折叠以及蛋白复合体亚基组装的研究中已崭露头角。
Different from mass spectrometry, whose separation is depended on the mass to charge, the ion mobility spectrometry(IMS) separate gaseous ions based on their size and shape. Thus the combination of IMS and MS can provide more information of protein structure. The travelling wave ion mobility spectrometry(TWIMS) is a new member of IMS family with good sensitivity and quick analysis rate. TWIMS-MS is suitable for analyzing the large molecular structure at biological concentration and within biological timescales, and its applications of protein complex structure and protein folding progress research have been paid great attention.