RADIOMETER ABL90 FLEX User Manual

5. Sensors and optical system ABL90 FLEX reference manual
5-44
Calibration of the optical system
The optical system is calibrated at two points using the following:
 The S7770 ctHb Calibration Solution with a known dye concentration to
determine the cuvette path length,
l.
 A transparent solution from the solution pack in the analyzer to determine the
zero point,
I
o
.
The zero point,
I
o
, is the current (or intensity) measured by the photodiode
array on the transparent solution in the cuvette. During this "blank calibration"
the
ctHb is calibrated to this zero point.
I
o
is measured automatically during system start up and during calibrations.
The cuvette path length (i.e. the length of the light path) is determined from
Lambert-Beer’s Law by measuring the absorbance of the colored dye present in
the tHb Calibration Solution (S7770), which has a known equivalent hemoglobin
concentration.
Beer’s Law: A = ε x C
dye
x l
where:
A = absorbance
ε = extinction coefficient
C
dye
= concentration of colored dye
l = length of light path
It is recommended that a tHb calibration is performed every three months. See
section
tHb calibration in chapter 6: Calibration in the ABL90 FLEX operator's
manual for further information about the tHb calibration.
Calibration
materials
Zero point
Cuvette path
length
tHb calibration
frequency

RADIOMETER ABL90 FLEX Specifications

General

Brand	RADIOMETER
Model	ABL90 FLEX
Category	Measuring Instruments
Language	English