Single port thermospray ion source with coaxial vapor flow

摘要

An apparatus for providing an ion vapor to be analyzed. A vaporizer probe, with a capillary tube extending into a vapor port of an ion source, has a release end which ejects a spray of vapor into a spray region of the ion source. Molecules of interest within the vapor may be ions pre- formed in solution or may be ionized by chemical ionization or plasma discharge ionization. A minor portion of the vapor is extracted from the spray chamber for mass analysis. The major portion is coaxially redirected from the spray chamber for return to the same port which receives the capillary tube of the vapor probe. A return tube is vacuum sealed to the port and is in fluid communication with a roughing pump which draws the ion vapor from the spray region through the ion source and the port for coaxial vapor backflow with the capillary tube. The ion source has a split-block structure for ease of both manufacture and routine maintenance.