| 摘要 |
In a tandem mass spectrometry system, a first mass analyzer filters parent ions using a wide mass passband with a narrow rejection notch defined according to a modulation format. A wide mass range of parent ions is transmitted to an ion fragmentation device. Daughter ions produced thereby are transmitted to a second mass analyzer to produce a daughter ion mass spectrum. The modulation of the measured daughter ion mass spectrum, when correlated with the passband modulation of the first mass analyzer (i.e., parent ion spectrum), allows definitive identification of each daughter mass peak with the appropriate parent ion. Due to the wide mass passband, the ion detector signal is in proportion to the increased ion flux passed by the first mass analyzer. |
| 主权项 |
1. A tandem mass spectrometry (MS) system, comprising:
a first mass analyzer configured for receiving a plurality of parent ions spanning a full parent mass range, wherein the full parent mass range comprises N parent mass sub-ranges; an ion fragmentation device; a second mass analyzer; an ion detector; and a computing device configured for: controlling the first mass analyzer, the ion fragmentation device, the second mass analyzer, and the ion detector according to a modulation format comprising the following steps:
(i) in a first iteration, transmitting a first packet of the parent ions received by the first mass analyzer to a fragmentation device, wherein the first packet spans the full parent mass range except for a first rejected sub-range, the first rejected sub-range being one of the N parent mass sub-ranges;(ii) fragmenting the parent ions of the first packet to produce a plurality of first daughter ions;(iii) measuring the first daughter ions to acquire first daughter spectral data;(iv) repeating steps (i) to (iii) for at least (N−1) additional iterations wherein, in each additional iteration, a new packet of the parent ions is transmitted to the fragmentation device, the new packet spans the full parent mass range except for a new rejected sub-range different from rejected sub-range of the first iteration and of any other previous iteration, the new packet is fragmented to produce a plurality of new daughter ions, and the new daughter ions are measured to acquire new daughter spectral data; selecting one of the N parent mass sub-ranges; and associating a group of measured daughter ions from the acquired daughter spectral data with the selected parent mass sub-range, wherein the group corresponds to daughter ions produced from parent ions of the selected parent mass sub-range. |
