The invention comprises apparatus for use with atmospheric pressure ionization sources in which an aerosol is formed from a solution of a sample. The aerosol is received in a hollow member and discharged outside the chamber of the ionization source in order to reduce contamination of the ionization source...http://www.google.de/patents/US8035088?utm_source=gb-gplus-sharePatent US8035088 - Device, apparatus and methods for mass spectrometry
