Method and apparatus for improving ion transmission into a mass spectrometer

摘要

An ion transfer device for transferring ions emerging from an electrospray ion source at atmosphere to a vacuum chamber includes an inner surface in the shape of a diverging conical duct. The ion transfer device has an entrance aperture for positioning proximate the exit port of the electrospray ion source emitter, the entrance aperture receiving the electrosprayed ions from the exit port of the electrospray ion source emitter at atmosphere, the diverging conical duct being an electrode toward which the ions migrate and having an exit aperture with an inner diameter larger than an inner diameter of its entrance aperture, the exit aperture enclosed in the vacuum chamber, the diverging conical duct transporting the ions from atmosphere to vacuum. The vacuum chamber can be a chamber of a vacuum housing enclosing a mass analyzer.

主权项

1. A method for transferring ions from atmosphere to a vacuum chamber of a mass spectra analysis system, the method comprising:
receiving ions from an ion source at atmosphere at an entrance aperture of a diverging duct electrode disposed proximate to the ion source; conveying the ions through a tube of the diverging duct electrode toward an exit aperture of the diverging duct electrode, the tube having a continuous inner surface defining an enclosed diverging channel between the entrance aperture and the exit aperture, and the exit aperture having an inner diameter larger than an inner diameter of the entrance aperture, the diverging channel narrowing the beam of ions; and injecting the ions from the exit aperture of the diverging duct electrode into the a vacuum chamber of a mass spectra analysis system, the exit aperture being operatively coupled to the vacuum chamber for transferring the ions thereto; and wherein the diverging channel has an angle of divergence greater than 0.5 degrees and less than about 5 degrees.