So arrangement B, i.e. connection in series of the columns in order (starting from the injector): a polar capillary column SUPEROX II FA (10 m × 0.53 mm × 1.20 μm) (4), deactivated capillary (2 m × 0.53 μm) (1), non-polar capillary column Rtx-1 (30 m × 0.53 mm × 5.0 μm) (3), and a short capillary (0.5 m × 0.32 mm) (5) was selected.