5
1.4
Measuring principles
1.4.1 Mechanical measuring principle
Special cuvettes with a steel ball inside are place on the measuring positions in instrument related racks.
As the measuring block is sloping slightly the ball always remains due to gravity at the deepest point of
the cuvette. In the height of this point there is a magnetic sensor. At first the sample is pipetted into a
measuring cuvette, then – if required – the first reagent is added and the incubation is started. The
instrument turns the cuvette with the adjusted speed around the longitudinal axis. When the incubation
is finished (parameter specific) the start reagent is added and the measurement is start simultaneously.
When the coagulation begins the growing clot pulls the ball out of the basic position and the magnetic
sensor detects a magnetic impulse which causes the end of the measurement.
1.4.2 Optical measuring principle
The photometry is basing on the fact that a part of the passing light (UV-VIS = UV and visible field ca. 200
- 900 nm wave length) is reduced through the liquid test sample. Here the own colouration of the probe
or the colouration of the probe by adding suitable reagents is used.The course of the colouration is
stored in the MC 10
plus
and evaluated by a special software according the test requirements.
photometer principle:
plasma before
plasma after
clot formation
clot formation
cuvett
e
measuring
block
ball
sensor
measuring
cell
Summary of Contents for MC10 PLUS
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