Setting up an mplc system

The sample is introduced into the system via an injection valve, but this - a much simpler and less expensive valve than that found in an hplc 75tem. We use a Rheodyne type 50 Teflon rotary valve, which will take a 3w rate of lOOml/min (Fig. 11.24). The pump and the column are -lanected to the red and white connectors respectively, whilst a sample load 33p (see below) is fitted to the black and yellow connectors. A Luer fitting. 3 attached to the blue connector, which is where the sample is introduced, - ing a syringe. The green connector is a vent and should be positioned so jiat effluent from it can be collected in a beaker or flask. 

In the load mode (anti-clockwise position), solvent from the pump jlet (red) passes directly out into the column (white). In this mode the sample inlet (blue) is connected through the load loop (black and yellow) to 

Anti-clockwise position - sample loaded onto loop by injection at port 6 

Clockwise position - sample flows onto column via sample loop 

Load loops are made very simply by coiling a length of 3mm Teflon tubing which holds the required volume and fitting ferules on either end -10, 25 and 50 ml loops are useful sizes to make. 

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