method for the analysis of one or more analytes present in a sample carried in a first fluid . the first fluid is combined with a first detector fluid and a second detector fluid to provide a fluid mixture which flows across the surface of an igniter . the analytes are ionized by means of an ionization process . the ion current is collected and measured at a collector electrode adjacent to the igniter . the flow of at least one of the first detector fluid and second detector fluid is modulated during an ignition sequence according to predetermined criteria so as to facilitate flame ignition .