Multiple ion injection in mass spectrometry

A method of mass spectrometric analysis, comprising steps of:

• fragmenting a first group of precursor ions having a first mass-to-charge ratio range using a first set of fragmentation parameters to produce a first group of product ions;
• fragmenting a second group of precursor ions having a second mass-to-charge ratio range using a second set of fragmentation parameters to produce a second group of product ions;
• accumulating and combining the first and second groups of product ions;
• and
• mass analyzing the combined product ions to generate a mass spectrum;
• wherein the first and second sets of fragmentation parameters differ from each other.

A method of mass spectrometric analysis, comprising:

• accumulating a first group of ions having a first mass-to-charge ratio range for a first accumulation period;
• accumulating a second group of ions having a second mass-to-charge ratio range for a second accumulation period, the first mass-to-charge ratio being different from the second mass-to-charge ratio and the first accumulation period being different from the second accumulation period;
• combining the accumulated first and second groups of ions, or ions derived therefrom;
• mass analyzing the combined ions to produce a mass spectrum;
• and
• adjusting intensities of peaks in the mass spectrum in accordance with the accumulation periods of the associated ion species.