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© Diatron MI Ltd. 2005
5 ROUTINE UTILIZATION and MEASURE
5.1 Measuring Process
5.1.1 Sample handling
As some time will usually elapse between collection of samples and counting, it is
necessary to preserve the sample with an anti-coagulant to prevent large groups of
cells forming into clots or lumps of cell matter that will clog the cell counter. Choice of
anti-coagulant is very important, as some anticoagulants will affect the shape and
size of blood cells. In general
EDTA
, preferably sodium or potassium based, is the
only anti-coagulant recommended for use with electronic blood counters.
Care must be taken when using homemade containers pre-dosed with EDTA. If the
container is not filled completely with blood, the ratio of EDTA to blood may reach a
level, which results in osmotic transfer from the RBCs, shrinking them.
The ratio of
EDTA to blood should not exceed 3 mg/ml
. Generally, we suggest using
manufactured sample tubes containing the necessary amount of EDTA and when
you take blood please take into account the specifications attached to them.
Important
! Sample tubes must be filled at least 7-8 mm height with blood
otherwise correct sampling is not guaranteed! Please observe,
that most sampling tubes usually have minimum and maximum
sampling volumes (blood level) indicated.
Attention! If you hurt yourself during analysis, biohazard substances can cause infection!
Always use protective rubber gloves!
To initiate analysis:
1. Invert closed sample tube 11 times to achieve homogenous sample. Do not
shake it, because micro-bubbles can form inside causing erroneous sampling!
2. Position the sample tube in the sample rotor, and push START key.
Closed vacutainer with sample blood
Sample tube with 5 ml control blood
Please wipe the mouth of the tube because the
bursting bubble can dirt the instrument with blood
causing measurement error at next sample
Figure 8. Sample tubes used in tube adapter
