An intermittent sample inlet device and methods for use of the intermittent sample inlet device are described that include an orifice plate with an entrance orifice and a rotating skimmer with a skimmer orifice, where the rotating skimmer is disposed between the orifice plate and a vacuum chamber wall. The rotating skimmer rotates so that the skimmer orifice intermittently aligns with the entrance orifice and allows an ion sample to pass through to a mass analyzer.