Dynamic pressure gradient modulation for comprehensive two-dimensional gas chromatography.

•A simple and effective means to accomplish differential flow modulation is introduced.•Total transfer (unit duty cycle) is achieved concomitant with full modulation.•Commercially available components are used to construct the low-cost modulator.•Narrow peaks are produced yielding high signal enhancements.•Separations of a 5 component test mixture, a 90 component test mixture and a diesel fuel are provided.