Method and system for providing a modifier to a curtain gas for a differential mobility spectrometer

摘要

A system including a differential mobility spectrometer is described as is a method of operating the system including the differential mobility spectrometer. The method and system involve a) providing ions to the differential mobility spectrometer; b) providing a drift gas to an inlet of the differential mobility spectrometer; c) adjusting a meter to define a selected volumetric flow rate for supplying a modifier liquid to the drift gas; and, d) supplying an actual volumetric flow rate of the modifier liquid to the drift gas, wherein the actual volumetric flow rate is within a percentage deviation from the selected volumetric flow rate.

主权项

1. A spectrometer system comprising:
an ion source for generating ions; a differential mobility spectrometer having an inlet and an outlet, the differential mobility spectrometer being situated downstream from said ion source for receiving ions from the ion source; a boundary member that surrounds the differential mobility spectrometer so as to define a curtain chamber, the inlet of the differential mobility spectrometer opening up into the curtain chamber, the outlet of the differential mobility spectrometer being configured so as to allow the ions to exit the curtain chamber; a curtain gas supply that provides a curtain gas at substantially atmospheric pressure, the curtain gas supply comprising a curtain gas conduit; a modifier supply that provides a modifier liquid, the modifier supply comprising a modifier conduit; a junction for merging the modifier conduit into the curtain gas conduit; the curtain gas conduit being fluidly connected downstream of the junction to the curtain chamber; a heater positioned inside the curtain chamber for heating the modifier liquid and the curtain gas; wherein said boundary member directs at least a portion of the curtain gas to the inlet of the differential mobility spectrometer so as to become a drift gas; and, wherein the modifier supply also comprises a meter for setting a selected volumetric flow rate of the modifier liquid, the meter being adjustable to change the selected volumetric flow rate, and the modifier supply being capable of maintaining an actual continuous volumetric flow rate that enters the curtain gas that is within a precision of about 2 percent of the selected volumetric flow rate.