Comparison of Internal Energy Deposition with Surface Acoustic Wave Nebulization (SAWN) and Electrospray Ionization

摘要

Surface Acoustic Wave Nebulization (SAWN) has been introduced as a new soft ionization method and applied to peptides. (S. Heron et al. Anal. Chem. 2010, 82, 3985-3989). MS data from SAWN and ESI showed a difference in the charge state distribution in that angiotensin produced lower charge states in SAWN. In addition, SAWN was found to successfully generate precursor ions for some fragile compounds. We now characterize the energy deposition in SAWN using dissociations of substituted benzylpyridinium ions as thermometer species. To provide a standard, ESI of benzylpyridinium ions was studied under similar conditions. Through controlling the parameters of SAWN, the ionization softness was compared at different sample flow rates, SAWN amplitudes, and interface temperatures.