Abstract: An analytical apparatus provides for the separation and analysis of a subset of ions from a mixture of ions in a gas. The apparatus includes an ion supply, such as an electrospray, which provides a population of variously charged ions. An analyzing chamber is coupled to the ion supply and includes a first wall with an inlet orifice for receiving the flow of variously charged ions, and a second wall opposed to the first wall. A laminar gas flow is established within the analyzing chamber along a flow axis. The second wall is provided with an outlet orifice that is displaced by a determined distance along the gas flow axis from the inlet orifice. A potential difference is applied between the first and second walls which causes the flow of ions, introduced via the inlet orifice, to migrate towards the outlet orifice.

Abstract: An analytical apparatus provides for the separation and analysis of a subset of ions from a mixture of ions in a gas. The apparatus includes an ion supply, such as an electrospray, which provides a population of variously charged ions. An analyzing chamber is coupled to the ion supply and includes a first wall with an inlet orifice for receiving the flow of variously charged ions, and a second wall opposed to the first wall. A laminar gas flow is established within the analyzing chamber along a flow axis. The second wall is provided with an outlet orifice that is displaced by a determined distance along the gas flow axis from the inlet orifice. A potential difference is applied between the first and second walls which causes the flow of ions, introduced via the inlet orifice, to migrate towards the outlet orifice.