US Patent 7537694 Method and device for multidimensional liquid chromatography

In a liquid chromatography, an electrolytic solution starts to be supplied from an injector toward a specimen in a first separating column to transfer components of the specimen from the first separating column toward one of first and second trap columns after a time period more than zero elapses from a time at which another eluting liquid starts to flow through the other one of the first and second trap columns toward a second separating column.