Collision cells and methods of using them
Certain embodiments described herein are directed to collision cells that comprise one or more integrated lenses. In some examples, a lens is coupled to two sections of a sectioned quadrature rod assembly, the lens comprising an aperture and a plurality of separate conductive elements disposed each one side of the lens, in which a respective disposed conductive element on one side of the lens is configured to electrically couple to a first, second, third, and fourth pole segments of the sectioned quadrature rod assembly.
1. A mass spectrometer comprising:
an ion source;
an ion detector; and
at least one ion collision cell fluidically coupled to the ion source at an entrance section of the ion collision cell and fluidically coupled to the ion detector at an exit section of the ion collision cell, the ion collision cell comprising a sectioned quadrature rod assembly configured to provide a collision section between the entrance section and the exit section, the sectioned quadrature rod assembly comprising first, second, third, and fourth pole segments in each region of the quadrature rod assembly, and a lens between segments of at least one of the entry section and the exit section, wherein the lens is coupled to and in contact with two adjacent regions of the sectioned quadrature rod assembly, wherein the lens comprises an aperture and a plurality of separate conductive elements disposed on each side of the lens, in which a respective disposed conductive element on each side of the lens contacts and is configured to electrically couple to one of the first, second, third, and fourth pole segments of the sectioned quadrature rod assembly to permit an RF field to continue at a pole/lens interface.
2. The mass spectrometer of claim 1 , further comprising a gas port fluidically coupled to the entrance section for introducing a gas into the collision cell.
3. The mass spectrometer of claim 1 , in which the pole segments are curved.
4. The mass spectrometer of claim 1 , in which the sectioned quadrature rod assembly is curved through about 180 degrees when the entrance section, the exit section and the collision section are coupled to each other.
5. The mass spectrometer of claim 1 , in which the separate conductive elements disposed on the lens are components of a printed circuit board.
6. The mass spectrometer of claim 5 , in which the printed circuit board is a 2-layer printed circuit board.
7. The mass spectrometer of claim 1 , in which the lens is operative as a gas restrictor, and in which the first and second poles segments are positioned in a top support plate and the third and fourth pole segments are positioned in a bottom plate, in which coupling of the top support plate to the bottom support plate provides a fluid tight seal between the top support plate and the bottom support plate and provides an opening, formed from the coupled top and bottom support plates, where ions may travel through.
8. The mass spectrometer of claim 1 , in which the lens is positioned between segments of the entrance section of the ion collision cell.
9. The mass spectrometer of claim 1 , in which the exit section comprises a gas port configured to introduce a cooling gas into the exit section.
10. The mass spectrometer of claim 1 , further comprising an additional lens between segments of at least one of the entrance section and the exit section of the sectioned quadrature rod assembly, the additional lens comprising an aperture and a plurality of separate conductive elements disposed on each side of the additional lens, in which a respective disposed conductive element on each side of the additional lens is configured to contact and electrically couple to one of the first, second, third, and fourth pole segments of adjacent regions of the sectioned quadrature rod assembly.
11. The mass spectrometer of claim 10 , in which the additional lens is positioned between segments of the exit section of the ion collision cell.
12. The mass spectrometer of claim 11 , further comprising a third lens in the exit section, in which the third lens comprises a central conductive element and a terminal connector electrically coupled to the central conductive element through a body of the third lens.
13. The mass spectrometer of claim 12 , in which the third lens is positioned downstream from the additional lens.
14. The mass spectrometer of claim 13 , further comprising a fourth lens in the exit section, in which the fourth lens comprises a central conductive element and a terminal connector electrically coupled to the central conductive element through a body of the fourth lens.
15. The mass spectrometer of claim 14 , in which the fourth lens is positioned downstream from the third lens.
16. The mass spectrometer of claim 15 , further comprising a first exit segment positioned between the additional lens and the third lens, a second exit segment positioned between the third lens and the fourth lens and a third exit segment coupled to the fourth lens.
17. The mass spectrometer of claim 16 , in which at least one of the exit segments is configured to receive a cooling gas.
18. The mass spectrometer of claim 17 , in which the third lens and the fourth lens are configured to push or pull ions through the collision cell.
19. The mass spectrometer of claim 18 , in which the third lens and the fourth lens are electrically coupled to a power source.
20. The mass spectrometer of claim 18 , in which the third lens and the fourth lens each comprises a 4-layered printed circuit board.