US 8,853,623 B2 · Electrostatic mass spectrometer with encoded frequent pulses

Abstract

A method, apparatus and algorithms are disclosed for operating an open electrostatic trap (E-trap) or a multi-pass TOF mass spectrometer with an extended flight path. A string of start pulses with non equal time intervals is employed for triggering ion packet injection into the analyzer, a long spectrum is acquired to accept ions from the entire string and a true spectrum is reconstructed by eliminating or accounting overlapping signals at the data analysis stage while using logical analysis of peak groups. The method is particularly useful for tandem mass spectrometry wherein spectra are sparse. The method improves the duty cycle, the dynamic range and the space charge throughput of the analyzer and of the detector, so as the response time of the E-trap analyzer. It allows flight extension without degrading E-trap sensitivity.

Claims24

Dependent claims

An electrostatic mass spectrometer comprising:

i. a pulsed ion source for ion packet formation;
ii. an ion detector;
iii. a multi-pass electrostatic mass analyzer providing an ion packet passage though said analyzer in a Z-direction and isochronous ion oscillations in the locally orthogonal direction X;
iv. a pulse string generator for triggering said pulsed ion source at time intervals between adjacent pulses being at or around ten (10) times shorter than a flight time of said ion packets in the analyzer, and wherein the time intervals between at least a portion of start pulses being unique within the peak time width ΔT on the detector thereby yielding at least partially overlapped spectral signals;
v. a data acquisition system recording of detector signal at the duration of said pulse string;
vi. a main pulse generator for triggering both-said data acquisition system and said pulse string generator;
and
vii. a spectral decoder for reconstructing the at least partially overlapped mass spectra based on the detector signal and on the information on the preset time intervals of said start pulses.

5 more elements

Dependencies are inferred from the claim text.

Electrostatic mass spectrometer with encoded frequent pulses

Life of this patent

Electrostatic mass spectrometer with encoded frequent pulses

Life of this patent

Abstract

Claims24