Soft ionization based on conditioned glow discharge for quantitative analysis

1. A method of mass spectrometric analysis, the method comprising the following steps:

producing either RF or DC glow discharge within a noble gas at gas pressure between 3 and 100 mBar;

sampling and conditioning glow discharge products within a gas flow through a conductive channel for removing charged particles while transferring excited Rydberg atoms;

mixing conditioned discharge products with analyte flow within an enclosed chamber at elevated temperatures above 150° Celsius for producing Penning reaction between analyte molecules and said Rydberg atoms to generate ions of said analyte;

sampling by a gas flow said analyte ions for mass spectrometric analysis;

providing a tubular electrode extending into an interior of a glow discharge chamber;

providing a capillary for sample introduction, wherein the capillary passes through the glow discharge chamber, protrudes through the tubular electrode, and at least partially passes through the enclosed chamber; and

at least one of the following steps:

(i) removing charge within said conductive channel caused by charging of an insulating surface protruding through said conductive channel;

(ii) coaxially mixing of analyte flow with the flow of conditioned plasma to form a mixed flow; or

(iii) cooling of said mixed flow within a sonic or supersonic jet for reducing a region of Penning ionization of the analyte molecules.

2. The method of claim 1 , wherein said ions of analyte are partially fragmented either at an ionization event or at a step of controllable collisional induced dissociation, wherein obtained fragment spectra are compared with library spectra of electron impact for analyte identification and for a structure elucidation.

3. The method of claim 2 , further comprising introducing less volatile compounds within a liquid or solid matrix to extend the range of analyte volatility whereat a matrix flux remains under 10 ng/sec and where the analyte sample is brought to a gas phase by one of the following steps:

(a) applying a rapid thermo desorption;

(b) applying pulsed laser desorption;

(c) applying nebulization of a liquid sample with removal of solvent vapors by side or counter gas while passing through aerosol; and

(d) applying nebulization at a flow rate under 10 nL/min past capillary electrophoresis or nano liquid chromatography.

4. A method as in claim 1 , further comprising a step of upstream tandem chromatographic separation of the list comprising: (i) GC×GC; (ii) LC-GC; (iii) LC-LC; (iv) LC-CE.

5. A method as in claim 2 , for the purpose of enhanced selectivity at analysis of complex mixtures, further comprising a step of mass or ion mobility selection of parent ions prior to the step of ion fragmentation.

6. A method as in claim 2 , further comprising a step of varying fragmentation energy.

7. A method as in one of claims 1 to 6 , for the purpose of enhanced analysis selectivity, further comprising a step of adding a reagent gas into the conductive channel, thus converting Rydberg ions into reagent ions.

8. A method as in claim 1 , further comprising a step of mass-spectrometric analysis of ionized analyte ions with a high resolution multi-reflecting time-of-flight mass spectrometer.

9. A method for assembling an ion source for a mass spectrometry apparatus, comprising:

providing a reactor chamber defining a sampling conditioning channel;

arranging a glow discharge chamber adjacent to the reactor chamber;

providing a tubular electrode extruding into an interior of the glow discharge chamber;

arranging a sampling nozzle at an outlet end of the reactor chamber;

providing a capillary for sample introduction, wherein the capillary passes through the glow discharge chamber, protrudes through the tubular electrode, and at least partially passes through the reactor chamber; and

arranging a mechanical fluid pump in a location to allow evacuation of gas, wherein the mechanical fluid pump evacuates the gas from the glow discharge chamber past the sampling nozzle.

10. The method of claim 9 , further comprising:

charging an insulated surface that protrudes through the sampling conditioning channel.

11. The method of claim 9 , wherein the gas evacuated by the mechanical fluid pump comprises a noble gas, and wherein the noble gas is pressurized within the glow discharge chamber prior to evacuation.

12. An ion source for a mass spectrometry apparatus, comprising:

reactor chamber defining a sampling conditioning channel;

a glow discharge chamber residing adjacent to the reactor chamber;

a tubular electrode extruding into an interior of the glow discharge chamber, wherein the tubular electrode receives a voltage;

a sample nozzle residing at an outlet end of the reactor chamber;

a capillary for sample introduction, wherein the capillary passes through the glow discharge chamber, protrudes through the tubular electrode, and at least partially passes through the reactor chamber; and

a mechanical fluid pump residing in a location to allow evacuation of gas, wherein the mechanical fluid pump evacuates the gas from the glow discharge chamber past the sampling nozzle.

13. The ion source of claim 12 , further comprising:

an insulated surface that protrudes through the sampling conditioning channel.

14. The ion source of claim 12 , wherein the gas evacuated by the mechanical fluid pump comprises a noble gas, and wherein the noble gas is pressurized within the glow discharge chamber prior to evacuation.

15. A method of conditioned glow discharge ionization, comprising:

arranging an enclosed ionization chamber for minimal outgassing;

heating the ionization chamber to an elevated temperature above 250 degrees Celsius;

feeding a noble gas into the ionization chamber at a flow rate between one hundred milliliters per minute and one thousand milliliters per minute;

evacuating the gas through a sampling conditioning channel;

inducing glow discharge between a tubular electrode and a counter-electrode, the tubular electrode extending into an interior of the ionization chamber;

inserting a capillary for sample introduction, the capillary having an insulating surface extending through the tubular electrode to stabilize the glow discharge inducement;

creating a gas flow through the sampling conditioning channel to move the induced glow discharge products;

protruding the insulating surface through the sampling conditioning channel;

wherein the capillary passes through the ionization chamber and at least partially passes through the sampling conditioning channel;

introducing an analyte sample;

mixing the analyte sample with the glow discharge products in close vicinity or within a throttle of a sampling aperture;

providing local cooling of the analyte sample within a gas cooling jet, wherein the gas cooling jet is formed within or around the sampling aperture; and

directing products to a mass spectrometer.

16. The method of claim 15 , wherein the capillary is a quartz capillary, and wherein the quartz capillary introduces the analyte sample.