Liquid junction apparatus for electrospray ionization

A liquid junction apparatus for electrospray ionization, comprising:

• an electrospray emitter having a liquid-entrance end which is fluidly connected via an electrospray emitter conduit to an emitter tip, from which liquid can be electrosprayed, the liquid-entrance end comprising an encasing with a conductive sheath,
• a capillary conduit assembly for conducting liquid to be electrosprayed that bottom-seals against the conductive sheath, and
• a union comprising an electrically conductive material and having a first side and a second side, the first side being designed and configured with a first opening to partially accommodate the electrospray emitter and the second side being designed and configured with a second opening to accommodate the capillary conduit assembly such that an exit of the capillary conduit assembly is positioned in opposing relation to the liquid-entrance end of the electrospray emitter to form a butt joint which facilitates transmitting liquid from the capillary conduit assembly to the electrospray emitter such that electrical contact of the liquid with the conductive sheath is established, wherein the union is connected to a voltage source and the conductive sheath is in electrical contact with the union such that the liquid at the butt joint is maintained at a predetermined electrical voltage level to facilitate electrospraying.