Patent ID: 7679053

Claim:
A method for introducing samples to a mass spectrometer from at least two sources, the method comprising: introducing a first of the samples through a first entrance point in a chamber in communication with a sampling inlet to the mass spectrometer, the first entrance point being defined in a boundary member that at least partially defines the chamber, the first entrance point being coaxial to the sampling inlet, the chamber having at least one region where field-free conditions are established, the first of the samples being introduced substantially adjacent to the sampling inlet; and introducing at least a second of the samples through at least one other entrance point defined in the chamber at a non-adjacent position to the sampling inlet; the chamber further defines a gas entrance for introducing a gas into the chamber, wherein a gas flow stream is established in which the gas flow stream flows partially toward the first entrance point and partially toward the sampling inlet, whereby at least the second of the samples is directed to the sampling inlet by the gas flow stream.