Metabonomics and Biomarkers Group, BioAnalytical Science Department, Nestle Research Centre, Nestec Limited, Vers-Chez-les-Blanc, 1000 Lausanne, Switzerland.
Anal Chem. 2009 Nov 15;81(22):9365-71. doi: 10.1021/ac901736j.
The present paper describes the performance of online, gas-phase hydrogen/deuterium exchange implemented in the ion mobility cell of a quadrupole time-of-flight mass spectrometer. Deuterium oxide and deuterated methanol were utilized to create deuterated vapor that is introduced into the ion mobility region of the mass spectrometer. Hydrogen/deuterium exchange occurs spontaneously in the milliseconds time frame without the need of switching the instrument into ion mobility mode. The exchange was studied in case of low molecular weight molecules and proteins. The observed number of exchanged hydrogens was equal to the number of theoretically exchangeable hydrogens for all low molecular weight compounds. This method needs only minimal instrumental modifications, is simple, cheap, environment friendly, compatible with ultraperformance liquid chromatography, and can be implemented on commercially available instruments. It does not compromise choice of liquid chromatographic solvents and accurate mass or parallel-fragmentation (MS(E)) methods. The performance of this method was compared to that of conventional alternatives where the deuterated solvent is introduced into the cone gas of the instrument. Although the degree of exchange was similar between the two methods, the "cone gas method" requires 10 times higher deuterated solvent volumes (50 muL/min) and offers reduced sensitivity in the tandem mass spectrometry (MS/MS) mode. The presented method is suggested as a standard future element of mass spectrometers to aid online structural characterization of unknowns and to study conformational changes of proteins with hydrogen/deuterium exchange.
本文描述了在四极杆飞行时间质谱仪的离子淌度池中实现的在线气相氢/氘交换的性能。使用重水和氘代甲醇来产生氘蒸气，将其引入质谱仪的离子淌度区域。氢/氘交换在毫秒时间框架内自发发生，无需将仪器切换到离子淌度模式。在低分子量分子和蛋白质的情况下研究了交换。对于所有低分子量化合物，观察到的交换氢原子数等于理论上可交换的氢原子数。该方法仅需要最小的仪器修改，简单、廉价、环保，与超高效液相色谱兼容，并且可以在市售仪器上实现。它不影响液相色谱溶剂的选择以及精确质量或平行碎裂（MS(E)）方法。该方法的性能与传统替代方法进行了比较，其中将氘化溶剂引入仪器的锥气体中。尽管两种方法的交换程度相似，但“锥气体方法”需要 10 倍更高的氘化溶剂体积（50 μL/min），并且在串联质谱（MS/MS）模式下提供的灵敏度降低。建议将该方法作为质谱仪的标准未来元素，以帮助在线未知物的结构表征，并研究蛋白质的构象变化与氢/氘交换。
