Flow scheme of LH 2.1
The dead volume is the volume that will be aspirated after the sample or sandwich solution to minimize sample loss during the injection. Accordingly, the dead volume is the volume that is situated between the needle and injection valve and therefore, also called needle tubing.
Normally A50807 is used as needle tubing and thus, the dead volume can be calculated by using the length and the inner diameter of the tubing. However, the correct dead volume can be also evaluated by the following procedure:
1) Set the Syringe Speed to a low value (e.g. 5mL/min).
2) Inject water with the deactivated sandwich option and with the dead volume type „Air“.
3) Observe the needle tubing and how the air plug is approaching the injection valve.
Choose and adapt the dead volume according to the needs of your injection routine. Would you like to have a small part of the dead volume inside the sample loop or shortly before the sample loop? Please mention that you can choose for your injection routines as dead volume type not only air but also sample or more useful sandwich solution to avoid the injection of air.
