horiba ABX MICROS ES60, Руководство пользователя

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Description & Technology
User Manual - RAB237AEN 3–7
3.3. CBC measurement principles
3.3.1. RBC/PLT
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The RBCs and PLTs are measured by an electronic impedance variation principle. This means that
an electronic field is generated around the micro-aperature in which the blood cells pass through.
The cells create a resistance in the electronic field as they pass through the calibrated micro-
aperture. This in turn causes an electronic pulse to be generated which is amplified, measured and
then mathematically calculated to create a numerical value.
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Firstly, the 28.3µl diluted blood sample is diluted in an electrolytic diluent (electronic current
conducting fluid), mixed, then pulled through a calibrated micro-aperture. There are two
electrodes placed on each side of the aperture and a constant electronic current passes between
them.
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As the blood cells pass through the aperture, they create resistance (impedence) in the electronic
field between the two electrodes. Since the current is constant and remains unchanged, the larger
the cell is, the "more" resistance it has. The smaller the cell is, the "less" resistance it has. The
voltage which measures the cells is proportional to the cell size. The larger the cell, the higher
the voltage will be. The smaller the cell, the lower the voltage will be.
◆
These electronic voltages vary in pulse size as cells pass through the aperture. The pulses are then
channeled according to pulse size. The pulses are then thresholded, grouped, then mathematically
calculated to create a numerical value for the determination of RBCs and PLTs.
Diag.3-9 Sample dilution ABX Micros ES60 CT/ABX Micros ES60 OT
Sample
ABX Diluent
ABX Lyse
RBC
PLT
WBC
HGB
CT
RBC
PLT
RBC
PLT
OT