What are the volumes of the Millar small animal Dip-well Cuvettes and why do they vary depending on the catheter I use?

We supply 2 different cuvette models for calibrating the volume of small animal PV catheters, the 910-1048 (11 wells) and the 910-1049 (6 wells).

It is essential that you use the known volumes specific to your Catheter and Cuvette model when performing a Dip-Well Cuvette (Volume) calibration, and not just the generic volume of the well. This is because depending on the electrode spacing of your Catheter, the Absolute Volume being measured within a Dip-Well will vary. 

 
Catheters with smaller spacing will measure less of the Well than catheters with larger spacing. For example, for the PVR-1035 (3.5mm spacing) and PVR-1045 (4.5mm spacing) when used with the 910-1049 Mouse Cuvette:
 
Catheter       Well 2 Known Volume
PVR-1035                 11uL
PVR-1045                 14.14uL
 
Therefore, if you assume the same volume value for both catheters, your Volume Calibration will be incorrect. Also it is important to make sure that the well contains enough blood to cover both pairs of electrodes.

Volume card for the 910-1048 can be found here , and 
Volume card for the 910-1049 can be found here

 
The ADInstruments PV Loop Module for LabChart 7 and higher comes with settings files with the known volumes of each small animal catheter type pre-written in to the Calibration Dialogue. 

For further technical assistance with this or any other issue, please contact ADInstruments Technical Support by clicking HERE