Method of calibrating ion signals

摘要

A method of mass or ion mobility spectrometry is disclosed comprising: providing a source 8 of analyte ions and a source of reference ions; providing a mass analyzer or ion mobility separator (IMS) 12; guiding the reference ions into an ion trap 10 and trapping the reference ions therein; guiding the analyte ions into the mass analyzer or IMS 12, wherein the analyte ions bypass the ion trap 10; and releasing reference ions from the ion trap into the mass analyser or IMS for analysis. The analyte ions and reference ions may be generated by the same ion source 8 or, alternatively, by first and second different ion sources (22 & 24 in Figure 5). Preferably, the trapped reference ions are controllably released from the ion trap 10 such that only a portion of said reference ions trapped in the ion trap are released at any given time.