Mass spectrometer for chemical ionization, electron impact ionization and mass spectrometry/mass spectrometry operation

A quadrupole mass spectrometer of the type having a first quadrupole mass analyzer provided with a first ion passage port and a second ion passage port located opposite to each other along the axis of the first quadrupole mass analyzer, comprising:

• first ion source means for generating first ions during a first phase operation,
• second ion source means for generating second ions during a second phase operation,
• first ion lens means directing at least a portion of said first ions to enter the first quadrupole mass analyzer at the first ion passage port during the first phase operation,
• and second ion lens means for directing at least a portion of said second ions to enter the first quadrupole mass analyzer at the second ion passage port during the second phase operation.

A quadrupole mass spectrometer comprising:

• ion source means for generating first ions during a first phase operation for mass spectrometry/mass spectrometry chemical analysis, and for generating second ions during a second phase operation,
• a first quadrupole mass filter,
• a second quadrupole mass filter,
• means forming a collision region,
• collision gas introduction means for introducing a collision gas into said collision region for favoring collision-induced reactions during the first phase operation,
• ion lens means operable during the first phase operation for directing at least some of said first ions moving through said collision region and said second quadrupole mass filter, said ion lens means also being operable during the second phase operation for simultaneously directing a first portion of said second ions moving through said first quadrupole mass filter and directing a second portion of said second ions moving through said second quadrupole mass filter,
• and ion detection means for operation during the first phase operation and the second phase operation.