Analytical Sciences

Abstract − Analytical Sciences, 24(11), 1399 (2008).

Biphasic Electrospray Ionization for the Study of Interfacial Complexes
Michel PRUDENT, Manuel A. MÉNDEZ, and Hubert H. GIRAULT
Laboratoire d'Electrochimie Physique et Analytique, Ecole Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland
Biphasic electrospray ionization (BESI) mass spectrometry is achieved by using a dual-channel microsprayer, where channels filled with different immiscible phases meet at the Taylor cone. Two types of interfacial complexation reactions have been studied: the interfacial complexation of aqueous lead ions by thioether crown molecules, and the interfacial complexation of an aqueous dipeptide by dibenzo-18-crown-6 as ionophore. The mass spectra also give valuable information on the stoichiometry of the complexation reaction.