The ultimate goal of analytical chemistry is to identify and quantify analytes with a wide range of polarity at trace to ultra-trace levels. MS has two goals: (i) detection and measurement of the analyte of interest at trace to ultra-trace levels, and (ii) structural elucidation of unknown analyte molecules via fragmentation. The first fragmentation process reduces the population of neutral analyte molecules, leading to fewer effective ions. So, sensitivity is expected to be reduced; yet, fragment ions can demonstrate superior sensitivity . Therefore, developing efficient ion sources that are softer, more resilient, compact, and capable of higher sensitivity is very desirable.