Ion focusing
The invention generally relates to apparatuses for focusing ions at or above ambient pressure and methods of use thereof. In certain embodiments, the invention provides an apparatus for focusing ions that includes an electrode having a cavity, at least one inlet within the electrode configured to operatively couple with an ionization source, such that discharge generated by the ionization source is injected into the cavity of the electrode, and an outlet. The cavity in the electrode is shaped such that upon application of voltage to the electrode, ions within the cavity are focused and directed to the outlet, which is positioned such that a proximal end of the outlet receives the focused ions and a distal end of the outlet is open to ambient pressure.
1. A method for analyzing a sample, the method comprising:
obtaining a sample;
generating ions of an analyte from the sample;
focusing the ions in a cavity of an electrode shaped to focus ions via application of a voltage to the electrode;
directing the focused ions through an outlet of the cavity into an inlet of a mass spectrometer due to the shape of the electrode; and
analyzing the ions.
2. The method according to claim 1 , wherein the cavity comprises an ellipsoidal shape.
3. The method according to claim 1 , wherein the outlet is grounded.
4. The method according to claim 1 , wherein the focusing step is performed at ambient pressure.
5. The method according to claim 1 , wherein the focusing step is performed above ambient pressure.
6. The method according to claim 1 , wherein the mass spectrometer is a bench-top mass spectrometer or a miniature mass spectrometer.
7. The method according to claim 6 , wherein the focused ions are continuously directed into the miniature mass spectrometer.
8. A method for collecting ions of an analyte of a sample, the method comprising:
obtaining a sample;
generating ions of an analyte from the sample;
focusing the ions at or above ambient pressure in a cavity of an electrode shaped to focus ions via application of a voltage to the electrode and direct the ions to an outlet of the cavity; and
collecting the focused ions.
9. The method according to claim 8 , wherein the collected ions form a crystal structure.
10. The method according to claim 9 , further comprising analyzing the crystal structure.
11. The method according to claim 10 , wherein analyzing is by x-ray crystallography.
12. A method for producing a reaction product, the method comprising:
obtaining two or more compounds;
generating ions for each of the compounds;
allowing the ions of the different compounds to interact to form reaction product ions;
focusing the product ions at or above ambient pressure in a cavity of an electrode shaped to focus ions via application of a voltage to the electrode and direct the ions to an outlet of the cavity; and
collecting focused material.
13. The method according to claim 12 , wherein the collected material forms a crystal structure.
14. The method according to claim 13 , further comprising analyzing the crystal structure.
15. The method according to claim 14 , wherein analyzing is by x-ray crystallography.