Systems and methods for relay ionization
The invention generally relates to systems and methods for relay ionization of a sample. In certain aspects, the invention provides systems that include an ion source that generates ions, a sample emitter configured to hold a sample, and a mass spectrometer. The system is configured such that the ions generated by the ion source are directed to interact with the sample emitter, thereby causing the sample to be discharged from the sample emitter and into the mass spectrometer.
1. A system for analyzing a sample, the system comprising:
a plurality of emitters, in which a first emitter relays ions onto a second emitter to produce an electrospray of a sample from the second emitter, wherein the first and second emitters are not in physical contact with each other, wherein the second emitter is a hollow body and the sample is held within the hollow body, wherein the second emitter is selected from the group consisting of: a hollow capillary in which a proximal and distal end are open; a hollow capillary in which a proximal end is sealed and a distal end is open; a steel needle comprising an inner bore; and
a mass spectrometer positioned to receive the electrosprayed sample.
2. The system according to claim 1 , wherein a proximal portion of the hollow body is open ended and the ions from the ion source are directed to interact with and enter a proximal end of the hollow body, thereby causing the sample to be discharged from a distal end of the second emitter and into the mass spectrometer.
3. The system according to claim 1 , wherein a proximal portion of the hollow body is sealed and the ions from the ion source are directed to interact with the proximal end of the hollow body, thereby causing the sample to be discharged from a distal end of the second emitter and into the mass spectrometer.
4. The system according to claim 1 , wherein the first emitter is an electrospray source.
5. The system according to claim 1 , wherein the first emitter is an plasma discharge source.
6. The system according to claim 1 , wherein the mass spectrometer is a bench-top or miniature mass spectrometer.
7. A method for analyzing a sample, the method comprising:
generating ions from a first emitter;
directing the ions to interact with a second emitter comprising a sample in order to cause the sample to be discharged from the second emitter, wherein the first and second emitters are not in physical contact with each other, wherein the second emitter is a hollow body and the sample is held within the hollow body, wherein the second emitter is selected from the group consisting of: a hollow capillary in which a proximal and distal end are open; a hollow capillary in which a proximal end is sealed and a distal end is open; a steel needle comprising an inner bore; and
analyzing the discharged sample in a mass spectrometer.
8. The method according to claim 7 , wherein a proximal portion of the hollow body is open ended and the ions from the ion source are directed to interact with and enter a proximal end of the hollow body, thereby causing the sample to be discharged from a distal end of the second emitter and into the mass spectrometer.
9. The method according to claim 7 , wherein a proximal portion of the hollow body is sealed and the ions from the ion source are directed to interact with the proximal end of the hollow body, thereby causing the sample to be discharged from a distal end of the second emitter and into the mass spectrometer.
10. The method according to claim 7 , wherein the first emitter is an electrospray source.
11. The method according to claim 7 , wherein the first emitter is an plasma discharge source.
12. The method according to claim 7 , wherein the sample is a biological sample.