Electrospray electrophoretic cell

Fig. 1.11 Electrospray as an electrophoretic cell. Adapted with permission from reference [28].

In fact, an electrospray ion source is more broadly capable than an electrophoretic cell to resolve multiple types of analytes since the ion source can generate gas phase ions from electrically neutral but polar compounds. Thus, when the analytes in the infused solution do not carry separable charge(s) but possess intrinsic dipoles, these compounds can be induced to interact with small cation(s) (e.g., H", Li , Na , NH4, K )or anion(s) (e.g., OH, Cl , formate, acetate) to yield adduct ions in the positive- or negative-ion mode, respectively, in a high electric field. The ionization efficiencies of these electrically neutral compounds depend on their inherent dipoles, the concentration of the small matrix ions, the affinity of the small ions for the analytes, and the electrochemical properties of the resultant adducts. ... 

Mellors, J.S., Jorabchi, K Smith, L.M., Ramsey, J.M. (2010) Integrated Microfluidic Device for Automated Single Cell Analysis Using Electrophoretic Separation and Electrospray Ionization Mass Spectrometry. Anal. Chem. 82 967-973. 

Mellors, J. S., K. Jorabchi, L. M. Smith, and J. M. Ramsey. 2010. Integrated microfluidic device for automated single cell analysis using electrophoretic separation and electrospray ionization mass spectrometry. Anal. Chem. 82 967-973. 

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