Systems and methods for hot plasma analysis of analytes using membrane desolvator
Systems and methods for measuring analytes (e.g., potassium) under hot plasma conditions of ICP analysis systems (e.g., ICP-MS, ICP-AES, etc.) are described, where a membrane desolvation unit and nitrogen flow gas are included to reduce Argon interferences. A system embodiment includes a heated spray chamber configured to receive a liquid sample and a sample gas to aerosolize the liquid sample; a first condenser coupled to the heated spray chamber; a second condenser coupled to the first condenser; a heated membrane coupled to the second condenser; and a gas introduction component coupled to the heated membrane to receive a flow of gas and to combine the flow of gas with a dried sample aerosol leaving the heated membrane, wherein the flow of gas is introduced at a rate of approximately 2.67 percent to approximately 20 percent of a flow rate of the sample gas.
1. A system for preparing a liquid sample for analysis by an inductively-coupled analysis system comprising:
a heated spray chamber configured to receive a liquid sample and a sample gas to aerosolize the liquid sample;
a first condenser coupled to the heated spray chamber;
a second condenser coupled to the first condenser;
a heated membrane coupled to the second condenser; and
a gas introduction component coupled to the heated membrane to receive a flow of gas and to combine the flow of gas with a dried sample aerosol leaving the heated membrane, wherein the flow of gas is introduced at a rate of approximately 2.67 percent to approximately 20 percent of a flow rate of the sample gas.
2. The system of claim 1 , wherein the sample gas is argon.
3. The system of claim 1 , wherein the flow of gas includes nitrogen.
4. The system of claim 1 , wherein the gas introduction component defines a channel through the gas introduction component from a first end of the gas introduction component to a second end of the gas introduction component through which the dried aerosol sample passes.
5. The system of claim 4 , wherein the gas introduction component defines a port coupled to the channel to introduce the flow of gas with the dried sample aerosol within the channel.
6. The system of claim 1 , wherein the gas introduction component defines an annular portion coupled with a port configured to receive the flow of gas.
7. The system of claim 6 , wherein the gas introduction component further defines a channel through which the dried aerosol sample passes, and wherein each of the annular portion and the channel are coupled to a mixing chamber to introduce the flow of gas and the dried aerosol sample.
8. The system of claim 1 , wherein the heated membrane includes a concentric arrangement of an inner tube and an outer tube separated by a membrane.
9. The system of claim 8 , wherein the membrane is substantially permeable to a solvent of the liquid sample.
10. The system of claim 8 , wherein the membrane is substantially impermeable to one or more metallic ions.
11. The system of claim 8 , wherein the membrane includes an expanded polytetrafluoroethylene (EPTFE) membrane.
12. A method for preparing a liquid sample for analysis by an inductively-coupled analysis system comprising:
introducing a liquid sample and a sample gas to a heated spray chamber to produce an aerosolized sample;
passing the aerosolized sample through at least one condenser coupled to the heated spray chamber;
subsequent to passing the aerosolized sample through at least one condenser coupled to the heated spray chamber, introducing the aerosolized sample to a heated membrane;
removing at least a portion of a solvent of the aerosolized sample in the heated membrane to produce a dried aerosolized sample; and
introducing a flow of gas to the dried aerosolized sample at a rate of approximately 2.67 percent to approximately 20 percent of a flow rate of the sample gas to produce a mixed sample.
13. The method of claim 12 , further comprising:
introducing the mixed sample to an inductively coupled plasma analysis system operating under hot plasma conditions.
14. The method of claim 12 , wherein the sample gas is argon.
15. The method of claim 12 , wherein the flow of gas includes nitrogen.
16. The method of claim 12 , wherein the liquid sample includes potassium ions.
17. The method of claim 12 , wherein introducing a liquid sample and a sample gas to a heated spray chamber to produce an aerosolized sample includes introducing the liquid sample to the heated spray chamber at a flow rate of approximately 20 μL/min to approximately 300 μL/min.
18. The method of claim 12 , wherein introducing a flow of gas to the dried aerosolized sample at a rate of approximately 2.67 percent to approximately 20 percent of a flow rate of the sample gas to produce a mixed sample includes introducing the flow of gas to the dried aerosolized sample at a flow rate of approximately 40 mL/min to approximately 100 mL/min.
19. The method of claim 12 , wherein introducing a flow of gas to the dried aerosolized sample at a rate of approximately 2.67 percent to approximately 20 percent of a flow rate of the sample gas to produce a mixed sample includes introducing the flow of gas to a gas introduction component coupled to the heated membrane, the gas introduction component includes an annular portion coupled with a port to receive the flow of gas, wherein the gas introduction component further defines a channel through which the dried aerosolized sample passes, and wherein each of the annular portion and the channel are coupled to a mixing chamber to introduce the flow of gas and the dried aerosolized sample.
20. The method of claim 12 , wherein the heated membrane includes a concentric arrangement of an inner tube and an outer tube separated by a membrane, wherein the membrane is substantially permeable to the solvent of the liquid sample and substantially impermeable to one or more metallic ions.