Capillary Chromatography - Apparatus for Heart Cutting 1

Apparatus for Heart Cutting


The apparatus is designed around a 6-port valve as shown in figures 24 and 25. There are two columns Column 1 and Column 2, usually coated with stationary phases that offer extreme interactivity (i.e., one would be a dispersive stationary phase such as OV101 and the other a strongly polar phase such as polyethylene glycol).In stage 1 the sampling system is connected to the column and the column exit connected to a suitable detector (detector 1) via a restriction. The separation is continuously monitored and when the peak(s) of interest are identified by detector 1, the valve is rotated and the column eluent diverted through a cooled trap (see figure 23). The trap can consist of a simple coil of metal capillary tube or a small, short packed tube containing a suitable adsorbent. After the material of interest has been trapped, the valve is rotated back to its original position. This returns the flow through column 1 back through to detector 1. At the same time carrier gas is fed through the trap to column 2 and then to detector 2.


Figure 24. Apparatus for Heart Cutting, Stage 1