nimbus8 - 7-7-2013 at 20:00
I have noticed that the volume gradations of pipettes either start from the bottom and go up in volume or start at the top and go down. When im
looking to buy serological pipettes the companies almost never specify how the gradations are set up.
Is there any terminology that differentiates between the 2 different types of volume gradations.
adamsium - 7-7-2013 at 20:43
I'm not sure if there is a terminology for the direction of the numbering, but an important distinction is where the numbering ends near the tip.
Serological pipettes have numbering that finishes right near the tip, so when the pipette is completely drained, the volume indicated by the initial
level has been dispensed, whereas a Mohr pipette has numbering that ends before the tip, on the cylindrical part, such that if it was completely
drained, a greater volume will have been dispensed due to the extra bit in the tip not being accounted for in the markings. Schott Duran refers to
these as 'partial outflow' (Mohr) and 'complete and partial outflow' (serological) pipettes.
[edit:] more appropriate for Reagents and Apparatus Acquisition?
[Edited on 8-7-2013 by adamsium]