another advantage to using apci over other ionization methods is that it allows for the high flow rates typical of standard bore hplc (0.2-2.0ml/min) to be used directly, often without diverting the larger fraction of volume to waste. additionally, apci can often be performed in a modified esi source. the ionization occurs in the gas phase, unlike esi, where the ionization occurs in the liquid phase. a potential advantage of apci is that it is possible to use a nonpolar solvent as a mobile phase solution, instead of a polar solvent, because the solvent and molecules of interest are converted to a gaseous state before reaching the corona discharge needle. because of apci involves a gas-phase chemistry, there is no need to use special conditions such as solvents, conductivity, ph for lc. apci appeared to be more versatile lc/ms interface and more compatible with reversed-phase lc than esi.