ABX Pentra 80 RAB108EA, User Manual

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Pentra 80
6–16
Pentra 80 - User Manual - RAB108EA
Tab. 6–4: WBC counts
3.3.3. LMNE Matrix count
The WBC and 5-part Differential
count in the flowcell are based on
3 essential principles:
• The double hydrodynamic slee-
ving «DHSS» which allows a linear
flow of the cells through the light
path (
ABX DIAGNOSTICS patent)
• The cell volume, which is measu-
rement by electrical current
(
impedance changes ).
• The measurement of Transmitted
light at a 0× angle, which allows a
measured response according to
the internal structure of each cell
and its absorbance, as unabsorbed
light passes through the spaces in
the nuclear material of each cell.
This is known as diffused light.
25ml of whole blood is delivered
into the LMNE chamber in a tan-
gential flow of EOSINOFIX. This
reagent lyses the RBC’s, stabilizes
WBC’s in their native forms, and
stains the Eosinophil nuclei with a
specific coloration for there measu-
rement in the matrix.
The solution is then stabilized with
Diluent and transferred into the
LMNE flowcell. Each cell is mea-
sured in absorbance
(cytochemistry) and resistive (vol-
ume) impedance changes
Fig. 6–18 DHSS principles
Technical characteristics of the WBC counts during the acquisition of the matrix
Initial blood volume 25 µl Method Impedance with hydrofocus
Vol. ABX Eosinofix 1000 µl Aperture diameter 60 µm
Diluent Volume 1000 µl Flow diameter 42 µm
Final dilution rate 1/80 Injection duration 12 s
Temperature of reaction 35°C Volume injected 72µl
Incubation duration 12s
Light abosrbance
measurement
Impedance
measurement