Even more intriguing, when nano-electrospray is conducted in high conductivity and low-flow rate conditions (not the conditions that provide the highest ion signal), peptide fragmentation occurred in the source . This was attributed to peptide ion emission directly from tiny first-generation highly charged droplets, i.e., to an ion evaporation scenario. For peptides, the charged residue and ion evaporation mechanism compete , and the sequence determines the propensity to overcharging by ion evaporation or chain ejection ). Thus, internal energy increase and fragmentation might indeed indicate the prevalence of an ion evaporation mechanism for some peptides.