DIALAB DIAcheck C1 - Principle of Measurment

Dialab GmbH
Operator's Manual DIAcheck series Rev-4 Page 13
1.4.4 PRINCIPLE OF MEASURMENT
The detection of plasma clotting is based on a photometric principle. No mechanical aids
like mixing bars are required. Blood plasma is filled into a cuvette. Special reagents are
added, which initiate the blood coagulation. The cuvette is transmitted by ultra violet light
during the coagulation process. When the sample starts to clot a change of light absorbance
is measured. The time from measurement start to change of light (turning point) is called
clotting time and expressed in seconds [s].
The conversion of coagulation time into a specific test unit is one using a linear, hyperbolic,
semi-logarithmic or double-logarithmic interpolation of the stored calibration points. The
current mathematical model is printed out in "TEST SETUP." Values outside the calibration
range are calculated by extrapolation and flagged as " * ".
Unit
Info
Decimal
places
Maximum
value
s
seconds
1
-
%
activity
1
180.0
U
units
0
999
INR
Int. ratio
2
30.00
R
ratio
2
30.00
NR
polish ratio
0
180
mg/dl
0
900
g/l
2
10.00
IE/ml
Int. Units
2
10.00
mg/l
2
10.00
µg/ml
3
7.000
ng/ml
0
7500
µg/l
0
7500
IU/mL
Int. Units
2
10.00
R = clotting time / normal time
NR = 100 *(normal time/clotting time)
INR = Ratio
ISI
(International Normal Ratio)
IU/mL = IE/mL = International Units (1.00 IU/mL = 100 % activity)