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. An ionization device, the device comprising:
an elongate tube that is at least one meter in length and comprises a proximal end configured to mate with an inlet of a mass spectrometer and open distal end, wherein the elongate tube further comprises an opening in a sidewall located at a distal portion of the elongate tube; and
a desorption electrospray ionization (DESI) source comprising a discharge tube;
wherein the device is configured such that a portion of the discharge tube is inserted through the sidewall of the elongate tube and terminates prior to the open distal end.
2. The ionization device of claim 1 , wherein the DESI source produces a DESI-active spray in a first direction within the elongate tube, and a velocity of the DESI-active spray in the first direction is reduced by a gas flow in an opposite direction generated in the elongate tube by a mass spectrometer that is coupled to the ionization device via the proximal end of the elongate tube.
3. The ionization device of claim 1 , wherein the elongate tube is a catheter.
4. The ionization device of claim 1 , wherein the portion of the discharge tube is sealed within the elongate tube.
5. The ionization device of claim 1 , wherein the distal portion of the elongate tube is configured to interact with a surface.
6. The ionization device of claim 5 , wherein the surface is tissue.
7. The ionization device of claim 2 , wherein the mass spectrometer is a bench top mass
spectrometer or a handheld mass spectrometer.
8. The ionization device of claim 2 , wherein the DESI-active spray is generated by an electrospray device.
9. The ionization device of claim 2 , wherein the source produces the DESI-active spray without voltage.
10. The ionization device of claim 2 , wherein the DESI-active spray comprises water.