A multi-dimensional GC/GCMS system performs separations using two
columns that have different chromatographic selectivity. When components of
interest are insufficiently separated on the first column, they can be selectively
introduced ("heart-cut") to a second chromatographic column with different
selectivity. This enables enhanced chromatographic separation that cannot be
attained in conventional single-column analysis. In addition, the precise
flow-switching technology, which is supported by a high-precision digital flow
controller, ensures heart-cut analysis with the high level of reproducibility
demanded of complex capillary GC separations.