Enclosed desorption electrospray ionization probes and method of use thereof
The invention generally relates to enclosed desorption electrospray ionization probes, systems, and methods. In certain embodiments, the invention provides a source of DESI-active spray, in which a distal portion of the source is enclosed within a transfer member such that the DESI-active spray is produced within the transfer member.
1. A system for analyzing a sample, the system comprising:
a source of DESI-active spray;
a transfer member;
a mass analyzer; and
a pump;
wherein the system is configured such that the transfer member is coupled to the mass analyzer and the pump, a distal portion of the source is enclosed within the transfer member such that the DESI-active spray is produced within the transfer member in a first direction and its velocity is reduced by the pump, which produces a gas flow in the transfer member in a direction opposite that of the first direction, and a laminar gas flow produced by the system transfers gas phase ions through the transfer member to the mass analyzer.
2. The system according to claim 1 , wherein the transfer member is a catheter.
3. The system according to claim 1 , wherein the distal portion is sealed within the transfer member.
4. The system according to claim 1 , wherein a distal portion of the transfer member is configured to interact with a surface.
5. The system according to claim 3 , wherein the surface is tissue.
6. The system according to claim 1 , wherein the mass analyzer is a bench top mass spectrometer or a handheld mass spectrometer.
7. The system according to claim 6 , wherein the mass analyzer is selected from the group consisting of: a quadrupole ion trap, a rectilinear ion trap, a cylindrical ion trap, a ion cyclotron resonance trap, an ORBITRAP mass spectrometer (ion trap mass analyzer consisting of an outer barrel-like electrode and a coaxial inner spindle-like electrode that traps ions in an orbital motion around the spindle), a time of flight, a Fourier Transform ion cyclotron resonance, and sectors.
8. The system according to claim 1 , wherein the DESI-active spray is generated by an electrospray device.
9. The system according to claim 1 , wherein the source produces the DESI-active spray without voltage.
10. The system according to claim 1 , wherein the DESI-active spray comprises water.
11. A method of analyzing a sample, the method comprising:
directing DESI-active spray droplets that are enclosed within a transfer member in a first direction onto a surface to interact with the surface and desorb an analyte from the surface and generate ions of the analyte, wherein the transfer member is in contact with the surface;
generating a gas flow in the transfer member via a pump in a direction opposite that of the first direction with enough counter-flow to reduce a velocity of the DESI-active spray;
transferring the ions via a laminar gas flow through the transfer member and into a mass analyzer; and
analyzing the ions in the mass analyzer.
12. The method according to claim 11 , wherein the transfer member is a catheter.
13. The method according to claim 11 , wherein the surface is tissue.
14. The method according to claim 11 , wherein the mass analyzer is a bench top mass spectrometer or a handheld mass spectrometer.
15. The method according to claim 14 , wherein the mass analyzer is selected from the group consisting of: a quadrupole ion trap, a rectilinear ion trap, a cylindrical ion trap, a ion cyclotron resonance trap, an ORBITRAP mass spectrometer (ion trap mass analyzer consisting of an outer barrel-like electrode and a coaxial inner spindle-like electrode that traps ions in an orbital motion around the spindle), a time of flight, a Fourier Transform ion cyclotron resonance, and sectors.
16. The method according to claim 11 , wherein the DESI-active spray is generated by an electrospray device.
17. The method according to claim 11 , wherein the source produces the DESI-active spray without voltage.
18. The method according to claim 17 , wherein the DESI-active spray comprises water.
19. A method of analyzing a tissue sample, the method comprising:
directing DESI-active spray droplets that are enclosed within a transfer member in a first direction onto a tissue to interact with the tissue and desorb an analyte from the tissue and generate ions of the analyte, wherein the DESI active spray comprises water and the DESI-active spray is generated without use of a voltage source;
generating a gas flow in the transfer member via a pump in a direction opposite that of the first direction with enough counter-flow to reduce a velocity of the DESI-active spray;
transferring the ions via a laminar gas flow through the transfer member and into a mass analyzer; and
analyzing the ions in the mass analyzer.