US 12,444,592 B2
Sample quantitation using a miniature mass spectrometer
Zheng Ouyang, West Lafayette, IN (US); Linfan Li, West Lafayette, IN (US); and Xiaoyu Zhou, West Lafayette, IN (US)
Assigned to Purdue Research Foundation, West Lafayette, IN (US)
Filed by Purdue Research Foundation, West Lafayette, IN (US)
Filed on Jan. 20, 2021, as Appl. No. 17/153,156.
Application 17/153,156 is a continuation of application No. 14/909,269, granted, now 10,930,481, previously published as PCT/US2014/049853, filed on Aug. 6, 2014.
Claims priority of provisional application 62/013,005, filed on Jun. 17, 2014.
Claims priority of provisional application 61/865,377, filed on Aug. 13, 2013.
Prior Publication US 2021/0166927 A1, Jun. 3, 2021
Int. Cl. H01J 49/00 (2006.01); H01J 49/04 (2006.01); H01J 49/42 (2006.01)
CPC H01J 49/0031 (2013.01) [H01J 49/0013 (2013.01); H01J 49/004 (2013.01); H01J 49/0422 (2013.01); H01J 49/4225 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A method for analyzing a sample and an internal standard in a miniature mass spectrometer, the method comprising:
generating sample ions and internal standard ions;
simultaneously transferring the sample and internal standard ions through a discontinuous sample introduction interface (DAPI) into a first ion trap of the miniature mass spectrometer, wherein the first ion trap is a first rectilinear ion trap that comprises top and bottom electrodes that are y electrodes and left and right electrodes that are x electrodes;
closing the discontinuous sample introduction interface;
sequentially transferring the sample and internal standard ions to a second ion trap of the miniature mass spectrometer, wherein the second ion trap is a second rectilinear ion trap that comprises top and bottom electrodes that are y electrodes and left and right electrodes that are x electrodes and wherein the first and second ion traps share a common end mesh electrode; and
sequentially analyzing within one second of each other the sample and internal standard ions in the second ion trap, wherein during a trapping step, a DC voltage is applied to the common end mesh electrode and single phase Radio Frequencies (RFs) of 1015 kHz and 995 kHz are applied on y electrodes of the first and second rectilinear ion traps, respectively, and after the trapping step and in order to then achieve an axial mass selective ejection, the ions trapped in the first rectilinear ion trap during a DAPI opening period undergo axial mass selective ejection toward the second rectilinear ion trap via application of one of the two following methods: (i) a separate RF scan with a resonance ejection by a dipolar AC, or (ii) an AC excitation with a separate steady RF.