In surface acoustic wave nebulization (SAWN), surface acoustic waves are produced via a piezoelectric substrate, which will interact with the liquid analyte put on the substrate to generate little droplets (Figure ). Analytes are nebulized as the droplets are charged statistically. The allure of the mass spectra is then similar to those obtained by ESI ). The internal energy distribution of ions produced by SAWN has been investigated ). Huang et al. measured the survival yield of substituted benzylpyridinium ions, and results were compared with ESI . The experiments were performed with a LTQ mass spectrometer where ESI and SAWN sources were placed in front of the heated capillary inlet, with the same mass spectrometers settings.