Calibration; Quality Control; Procedure Stepwise - Chrono-Log 490 4+4 Instruction Manual

ACTIVATE Bar – provides the ability to control each test
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individually or in sets of 2 or 4 channels, eliminating the
risk of some samples sitting in test well for extended
period of time before tests are started.
1. To run up to Eight (8) tests at the same time:
a. After a 3-minute incubation, place test cuvettes
in PRP test wells – from 1 to 8 channels
b. Click on "Activate" Bar and press the Set Baseline
button for each channel.
c. Monitor all tracings for stability.
d. Once tracings are stable and, if a clean test
screen is needed, Click on "Aggregometer" and
"Reset" for all channels.
e. If required that the Baseline setting appear on
test printout, press Set Baseline for all channels.
f. Click on "Start" Bar for Channel 1 and add
reagent.
g. If Baseline setting not required on test printout,
Click on the "Start" Bar for Channel 1 and add
reagent.
h. Repeat "e and f" or "g" for remaining channels.
2. To run tests in 4 channel sets:
a. After a 3-minute incubation, place 4 test
cuvette(s) in PRP test well(s) in Channels 1 thru 4.
b. Click on "Activate" Bar and press the Set Baseline
for Channels 1 thru 4.
c. Monitor tracings for stability. [NOTE: At this
point, place 4 additional test cuvettes in
Incubation wells for Channels 5 thru 8 for a 3-
minute incubation.]
d. Once tracings are stable and, if a clean test
screen is needed, Click on "Aggregometer" and
"Reset" for Channels 1 thru 4.
e. If required that the Baseline setting appear on
test printout, press Set Baseline for Channels 1
thru 4.
f. Click on "Start" Bar for Channel 1 and add
reagent.
g. If Baseline setting not required on test printout,
Click on the "Start" bar for Channel 1 and add
reagent.
h. Repeat "e and f" or "g" for remaining channels.
i. After 3-incubation, place 4 test cuvette(s) in PRP
test well(s) in Channels 5 thru 8.
j. Repeat "b" thru "h" for Channels 5 thru 8.
5. Micro-Pipettes with 2-Stop Control Button
a. Description of 2 Stops
1) First Stop – The measuring stroke for aspirating
and dispensing the selected volume
2) Second Stop – To blow out any liquid remaining
in the pipette tip after dispensing.
b. Volume Setting
When adjusting the volume setting from a higher value
to a lower value, turn the knob past the desired
volume and then back to the required setting.
c. Filling the Pipette Tip
1) Press the control button down to the first stop
2) Immerse the pipette tip vertically into the liquid
3) Aspirate and dispense the liquid three times by
using the first stop only.
Document # 49044IM1
Revision 7.5
Dated February 16, 2017
4) Remove the tip slowly from the liquid. For large
volumes, wait approximately 3 seconds before
removing the tip from the liquid.
5) Wipe off the outside of the tip with a lint-free
tissue to remove any excess liquid, taking
precaution that the tissue does not touch the tip
opening.
NOTE: When pipetting Whole Blood, PRP or Platelets do NOT
aspirate/dispense 3 times. Only take up the sample one time.
d. Dispensing
Place the pipette tip into the cuvette, so that the end
of the tip is immersed in the sample.
1) Slightly angle the pipette so that the tip is angled
to touch the wall of the cuvette.
2) Press the control button down to the first stop,
then press the control button down to the
second stop (blow-out) to empty the pipette tip.
3) Hold the control button down at the second
stop and, while keeping the pipette tip at a slight
angle, pull the pipette tip out of the sample.
4) Once the pipette tip is completely outside of
the cuvette, release the control button.

CALIBRATION:

For testing platelets, the Optical mode is calibrated automatically
during the testing procedure by the setting of 0% (PRP) and 100%
(PPP) baselines.

QUALITY CONTROL:

It is good laboratory practice to run a drug free normal control
whenever reagents are reconstituted or thawed. Test results
should fall within Normal Ranges established in each laboratory.
If desired, positive controls can be provided by collecting samples
from aspirin volunteers or subjects previously diagnosed with a
platelet disorder.
Positive controls can also be made in-vitro by the addition of
aspirin or the depletion of plasma. A final concentration of 1 mM
aspirin in citrated blood will inhibit the response to arachidonic
acid. Centrifugation, removal of platelet poor plasma and
replacement with an equal volume of saline, while leaving the
buffy coat in place will inhibit response to Ristocetin.
PROCEDURE - STEPWISE:
1. Check Aggregometer to be sure heater block has stabilized
to 37°C.
2. Place P/N 311 Stir bars in P/N 312 Cuvettes. Put cuvettes
containing stir bar in the incubation wells to warm up.
3. For testing the same donor in all channels, set all channels to
reference channel #1 PPP. [If each channel is set to its own
PPP, a cuvette with 500 µL PPP is required for each channel.]
SELECT Pushbutton(s) – allows for toggling between the Stirring
Speed, Temperature and PPP/Reference Settings.
SET Pushbutton(s) - sets the Stirring Speed, Temperature and
PPP/Reference, depending on which feature is selected. Each
time the SET button is pushed, the selected function is
incremented until it reaches the maximum setting.
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