Abstract: An interface between a liquid chromatograph and a mass spectrometer is provided for conducting a liquid stream from the chromatograph to the spectrometer. The stream passes from the chromatograph continuously along a tapered concentrator wire toward the narrow end of the wire. The stream is heated in order to evaporate solvent therefrom and to increase the concentration of the solute therein. When the stream reaches the narrow end of the wire, the vacuum created by the mass spectrometer draws the stream through an elongated capillary tube which has a pointed carrier wire positioned therein. A gap is provided in the tube where the tube and the carrier wire intersect the concentrator wire. The capillary tube is either formed with a reduced diameter at one end adjacent the spectrometer or the carrier wire has a ball of solder at that end in order to partially restrict the flow through the tube.