LC/MS of protein mixture containing (1) 17 μM RNase A, (2) 13 μM ubiquitin, (3) 7.7 μM lysozyme, (4) 15 μM BSA, (5) 6.5 μM myoglobin, and (6) 7.6 μM carbonic anhydrase with 0.1% TFA and (a) 0.1% m-NBA and 0.1% 3-NPEA, and (b) 0.1% MOZ and 0.1% TES. No supercharging agent was added to the measurements represented by the bottom trace in both (a) and (b).