US 11,892,433 B2
Electrospray current measurement in the nanospray and microspray regime
Dale Lindseth, Rice, MN (US); Joshua A. Silveira, Gilroy, CA (US); Michael L. Poltash, Fremont, CA (US); Eloy R. Wouters, San Jose, CA (US); and David E. Minkler, Campbell, CA (US)
Assigned to Thermo Finnigan LLC, San Jose, CA (US)
Filed by Thermo Finnigan LLC, San Jose, CA (US)
Filed on Aug. 2, 2021, as Appl. No. 17/391,880.
Prior Publication US 2023/0030920 A1, Feb. 2, 2023
Int. Cl. H01J 49/16 (2006.01); G01N 30/72 (2006.01); G01N 30/02 (2006.01)
CPC G01N 30/7266 (2013.01) [H01J 49/165 (2013.01); G01N 2030/027 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus for electrospray ionization of a fluid sample, comprising:
a fluid union;
a fluid column coupled with a first port and configured to receive a fluid sample and separate molecules in the fluid sample to produce a separated fluid sample, wherein the fluid column is configured to transfer the separated fluid sample into the fluid union via the first port;
a power source coupled with the fluid union and configured to apply a voltage potential to the fluid union sufficient to ionize the fluid sample to form an ionized fluid sample, wherein the power source is further coupled with the first port and configured to apply the voltage potential to the first port to restrict current leakage from the fluid union;
an electrospray emitter coupled with the fluid union, wherein the electrospray emitter is configured to emit the ionized fluid sample; and
a current sensing circuit disposed between the power source and the fluid union, wherein the current sensing circuit is configured to determine an electrical current flow between the power source and the fluid union.