A process for ionizing a liquid can comprising flowing the liquid through a capillary wire bonding tip and applying sufficient voltage to electrospray the liquid sample as it exits therefrom. The electrospray ionization process can further involve passing a liquid sample through an axially disposed aperture in a ceramic capillary wire bonding tip in which the terminus of the aperture flares into a bell-shape where the liquid sample exits therefrom. An add-on device can include gel electroelution and separating devices, and a ceramic capillary sample injection tip for carrying out the aforesaid electrospray ionization process. An adjustably mounted cartridge can also be provided with the add-on device for interchangeably receiving the ceramic capillary sample injection tip.