Back to results
US 6,057,543 AGranted
Time-of-flight mass spectrometry analysis of biomolecules
AssigneePerSeptive Biosystems, Inc.
InventorsMarvin L. Vestal, Peter Juhasz
Life of this patent
Estimating the term…
Abstract
A time-of-flight mass spectrometer for measuring the mass-to-charge ratio of a sample molecule is described. The spectrometer provides independent control of the electric field experienced by the sample before and during ion extraction. Methods of mass spectrometry utilizing the principles of this invention reduce matrix background, induce fast fragmentation, and control the transfer of energy prior to ion extraction.
Claims13
A method of improving mass resolution in time-of-flight mass spectrometry by compensating for an initial velocity distribution of ions, the method comprising:
- a) applying a potential to a sample holder;
- b) applying a potential to a first element spaced apart from the sample holder which, together with the potential on the sample holder, defines a first electric field between the sample holder and the first element;
- c) ionizing a sample proximately disposed to the holder with a laser to form sample ions;
- d) applying a second potential to either the sample holder or the first element at a predetermined time subsequent to steps a) through c) which, together with the potential on the first element, defines a second electric field between the sample holder and the first element, and which extracts the ions from the first element after the predetermined time;
- and
- e) energizing an ion reflector spaced apart from the first element, wherein the first and second electric fields and the predetermined time are chosen such that a flight time of extracted ions of like mass-to-charge ratio from the reflector to a detector will be substantially independent of the initial velocity, thereby improving mass resolution.
3 more elements
Dependencies are inferred from the claim text.