Electrosprays intense electric field

Electrospray ionization (ESI) refers to the overall process by which an intense electric field disperses a sample liquid into a bath gas as a fine spray of highly charged droplets. Evaporation of those charged droplets produces gas-phase ions by mechanisms that remain the subject of much argument and debate. The ESI is a complex of independent component processes, the two most important of which are electrospray dispersion, the electrostatic dispersion of sample liquid into charged droplets, and ionization, the transformation of solute species in those droplets to free ions in the gas phase. 

Electrospray, also called electrohydrodynamic or electrostatic spray, is an atomization technique in which liquids are dispersed solely by the application of high voltages. A simple electrospray setup is shown in Fig. 4. A liquid flows into a metal capillary tube charged to the kilovolt range and emerges from the tip as a conical meniscus, known as a Taylor cone, due to the intense electric field (Fig. 5). An unstable jet extends continuously from the apex of the cone and disperses into charged droplets further downstream. Electrosprays have been used in industrial... 

An electrospray is generally produced by the application of an electric field to a small flow of liquid from a capillary tube toward a counter electrode. The principles of electrospray as applicable to mass spectrometry and the mechanisms involved have been a subject of intense debate over the last decade and have been addressed even before that. This is evident from the discussions in the 2000 issue of the Journal of Mass Spectrometry (e.g., Mora11), the book by Cole,12 and several reviews.8,10 13 14 Here we present a summary encapsulating the relevant observations and direct the readers to the above articles for a more elaborate account. 

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