US Patent 9683975 Volumetric flow regulation in multi-dimensional liquid analysis systems

A multi-dimensional liquid analysis system includes a first dimension system and a second dimension system, wherein outflow from the first dimension system is separated at a flow splitter under controlled conditions. The flow splitter separates the first dimension outflow into first and second split outlet flows, with one of the split outlet flows being metered to a designated flow rate with a flow metering device disposed downstream from the flow splitter. The flow metering device selectively closes or opens an outlet flow path to define a volumetric flow rate along that outlet flow path, so that the other split outlet flow is correspondingly controlled.