Electrochemistry and electric field as origins of multiply charged ions

2 Electrochemistry and Electric Field as Origins of Multiply Charged Ions 

Charges of ions generated by ESI do not reflect the charge state of compounds in the analysed solution, but are the result of both charge accumulation in the droplets and charge 

MicroESI Q-TOF spectrum of assemblies of vanillyl alcohol oxidase obtained by W.J.H. van Berkel and co-workers [68], At the left, an octamer-dimer of 1.02 MDa molecular weight, and at the right, the octamer-trimer of 1.53 MDa. Reproduced courtesy of Dr. A.J.R. Heck. 

At pH 10, positive ions can be observed too. Additional peaks in the spectra result from a modification of the protein at basic pH (loss of heme group). 

it is worthy of consideration to try to acidify a solution with a view to a better detection of negative ions, and vice versa. Indeed, both II301 and OH have high limit equivalent conductivities, as shown in Table 1.3. 

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