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© 1990-2002 J.Paul Robinson, Purdue University  BMS 631 – LECTURE007.PPT
Fluidics Systems
Positive Pressure Systems
•  Based upon differential pressure
     between sample and sheath fluid.
•  Require balanced positive pressure
     via either air or nitrogen
•  Flow rate varies between 6-10 ms-1
+ + +
+ + +
+ + +
Positive Displacement Syringe Systems
•  1-2 ms-1 flow rate
•  Fixed volume (50 l or 100 l)
•  Absolute number calculations possible
•  Usually fully enclosed flow cells
100 l
Sample loop
Sample
Waste
Flowcell
3-way valve
Syringe