In ESI, a solution containing the analyte(s) flows through a capillary held at several kilovolts. At the capillary tip, a conical droplet (Taylor cone) forms and, aided by coaxial gas flow, emits a fine mist of droplets. There is considerable debate regarding the formation of gas-phase ions via the ESI process, but the general consensus is that a highly charged droplet forms initially, which then undergoes multiple cycles of solvent evaporation and fission to produce ions. ESI results in little to no fragmentation, and offers fine control over spray and solution conditions to produce clusters with sufficient concentration for MS detection.