Preliminary results for the analytical use of electrospray mass spectrometry (ES-MS) for elemental analysis are presented. Spectra with the declustered plus-one ion (M<sup>+</sup>) as the dominant species have been measured for the alkali metals (Li, Na, K, Rb, and Cs) and for several transition metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, and Cd) in both aqueous and methanol solvents. A number of background ions are also observed including MH<sup>+</sup>, MO<sup>+</sup>, MOH<sup>+</sup>, and MOH(H<sub>2</sub>O)<sup>+</sup>. For vanadyl sulfate and uranyl nitrate, ES conditions can be adjusted to produce VO<sup>+</sup> and UO<sub>2</sub><sup>+</sup> as the dominant ions in the mass spectra, indicating that direct speciation of inorganic solution components is possible. On the basis of these preliminary results, it appears that electrospray may offer a low-cost and simple generic ion source for elemental mass spectrometry.
George R. Agnes and Gary Horlick, "Electrospray Mass Spectrometry as a Technique for Elemental Analysis: Preliminary Results," Appl. Spectrosc. 46, 401-406 (1992)