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. An system for collecting molecules, the apparatus comprising,
an apparatus comprising:
an electrode comprising a cavity;
at least one inlet within the electrode configured to operatively couple with an ionization source, such that discharge generated by the source is injected into the cavity of the electrode;
an outlet; wherein 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; and
a moving stage operably associated with the outlet to receive the focused ions.
2. The apparatus according to claim 1 , wherein the interior of the cavity comprises an ellipsoidal shape.
3. The apparatus according to claim 2 , wherein the cavity is pressurized.
4. The apparatus according to claim 2 , wherein the outlet is connected to the electrode.
5. The apparatus according to claim 2 , wherein the outlet is spaced from the electrode.
6. The apparatus according to claim 2 , wherein the outlet is grounded.
7. The apparatus according to claim 1 , further comprising a gas inlet.
8. The apparatus according to claim 1 , further comprising a plurality of ring electrodes positioned within an interior portion of the cavity such that they are aligned with the outlet, wherein the electrodes are arranged in order of decreasing inner diameter with respect to the outlet.