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Estimated Efficiency and Run Time
Efficiency (%) and Run Time (minutes) are automatically calculated based upon the values entered in
the Settings section. If the calculated efficiency percentage results in a situation where multi-imaging of
particles is likely to occur, an error message will be displayed. The Flow Rate and/or the AutoImage
Rate will need to be adjusted to produce a set of conditions that does not potentially result in the multi-
imaging of particles. For standard (not field-of-view) flow cells, the Efficiency can not reach 100% due
to the width of the flow cell (which will have areas outside of the camera’s field of view). To obtain
Efficiency values that approach 100%, a field-of-view flow cell must be utilized as the fluid channel lies
entirely in the camera’s field of view. Finally, the calculators on this screen are provided when a syringe
pump is not installed but in that scenario their accuracy depends of the accuracy of the user-provided
flow rate.
Priming
Machine Prime
– Automatically pulls sample from the sample introduction port (pipette tip or funnel)
into the flow cell and into the camera’s field of view. In order for Machine Prime to function correctly,
which was designed using a fluid with a viscosity similar to water, there are two items to check before
use:
·
Ensure that the tube lengths (both above and below the flow cell) are measured accurately. It is
recommended that a minimum resolution of 0.25 cm be used when inputting these lengths.
·
When adding the sample into the introduction port (pipette tip or funnel) ensure that the bottom
or leading meniscus of the sample is located between the top of the flow cell tube and the bottom
of the pipette or funnel tip. The position of the sample is important as it will allow the correct
amount of volume to be drawn down to the flow cell. If the sample level is above the top of the
flow cell tube, then there is a risk of imaging a dry flow cell at the start of the run. If the sample
level is below the bottom of the pipette tip, then the system may run out of sample before the
analysis is complete.
Manual Prime with Sample
– The sample has already been drawn into the imaging path in the flow
cell.
Manual Prime with Non-Sample
– A buffer solution, such as distilled water, that contains no sample
of interest is drawn into the flow cell and the sample to be tested is added above/on top of this buffer.
When a non-sample priming fluid is used before running the sample of interest, the resulting dilution of
the target sample is accounted for by the software. If using a non-syringe pump, this priming method
will result in the most accurate particle count. Note that the length of the tubing from the sample
introduction vessel (funnel or pipette tip) to the top of the flow cell must be measured (cm) and entered
correctly.
Sample Dilution
The sample fluid was diluted or concentrated
- This
Dilution ratio
is used to account for sample
dilution or concentration. For example, if a sample is diluted to 50% of the original concentration, this
value should be set to 0.5000 to allow the software to correctly calculate statistics on the original
concentration.
