Combined mass and differential mobility spectrometry and associated methods, systems, and devices
The invention relates generally to systems, methods and devices for analyzing samples and, more particularly, to systems using a mass analyzer in combination with a differential mobility spectrometer to enhance the analysis process of constituents of a sample.
1. A sample analysis system comprising,
at least one ion mobility based analyzer, the at least one ion mobility based analyzer having a differential ion mobility based filter for generating a time-varying electric field and compensation field through which ions of the sample flow continuously along a flow path, the differential ion mobility based filter having at least two flat plate electrodes;
an ion mobility based detector for detecting ions in the flow path;
at least one time-of-flight mass analyzer for detecting ions delivered directly from the at least one ion mobility based analyzer; and
a controller for varying the compensation field of the differential ion mobility based filter by stepping a compensation voltage over a single range of compensation voltages and for generating a time-of-flight mass spectra for each step of the compensation voltages in the range of compensation voltages;
wherein the ions differential mobility behavior is based on molecular modeling calculations.
2. The system of claim 1 , wherein the controller is configured for generating a first standard spectra based on the ion mobility of at least one known ion species.
3. The system of claim 2 , wherein the controller is configured for generating a second standard mass spectra based on the mass-to-charge ratio of at least one known ion species.
4. The system of claim 2 comprising a data store for storing a set of conditions associated with the at least one ion intensity peak of the first standard spectra.
5. The system of claim 4 , wherein the set of conditions include at least one of a time-varying voltage and a compensation voltage for the differential ion mobility based filter.
6. The system of claim 4 , wherein the set of conditions includes at least one of a type of dopant, a concentration of a dopant, pressure, temperature, flow rate, and mass analyzer voltages associated with generating the first and second spectra.
7. The system of claim 2 , wherein the controller is configured for comparing a generated ion mobility spectra to the first standard spectra to identify at least one ion species.
8. The system of claim 3 wherein the controller is configured for comparing the mass spectra to the second standard mass spectra to identify at least one ion species.
9. The system of claim 1 comprising at least one electrospray ionization source.
10. The system of claim 9 , wherein the electrospray ionization source includes a direct infusion ionization source.
11. A method for analyzing all constituents of a sample comprising:
filtering based on a planar differential ion mobility of ions of the sample by stepping a compensation voltage applied to one or more planar filter electrodes over a single range of compensation voltages, and
generating at least two spectra including a first spectra based on the mass-to-charge ratio and a second spectra based on ion mobility of the filtered ions of the sample at each step of the compensation voltage in the single range of compensation voltages;
wherein the ions differential mobility behavior is based on molecular modeling calculations.
12. The method of claim 11 , further comprising stepping through a plurality of compensation voltages and acquiring mass-to-charge spectra at each of the plurality of compensation voltages.
13. The method of claim 11 , wherein the first spectra based on the mass-to-charge ratio is generated from at least one signal from a mass analyzer.
14. The system of claim 1 , wherein the mass spectra is generated from at least one signal from the at least one mass analyzer.
15. The method of claim 11 , wherein the first spectra based on the mass-to-charge ratio is obtained from a time-of-flight mass analyzer.