Why does the blue stopper have to be removed when filling the testing capillary with a low volume sample?
It is necessary to remove the separating valve (blue stopper) in order to equalize the pressure on both sides of the motility channel of the capillary. This will insure that the sample is in the correct area of the capillary and it prevents backflow into adjoining areas of the capillary. The accuracy of the motility reading may be impacted if the separating valve is not removed.
