Turner Designs AquaFluor, Руководство пользователя

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Aqua Fluor
®
U
ser’s Manual
13
4 Sample Analysis Guidelines
4.1 Handling Samples

Take care not to spill samples into the sample chamber. Wipe up any spills promptly.

The cuvette MUST BE DRY on the outside when taking readings. Any moisture or
condensation on the outside of the cuvette can affect the reading.

Fill the cuvette with at least 3mL solution volume or at least 3/4 full. Significant error in
the readings can result if the cuvette contains less than this minimum volume.

The Aqua Fluor
®
is very sensitive and even small amounts of material from a previous
sample may contaminate the sample and result in errors. Use a clean cuvette for all
readings. If you are using the same cuvette for your samples it is very important that
you thoroughly rinse the cuvette between samples. A good way to confirm the cuvette
cleanliness is to read a blank solution. If the reading is higher than the normal blank
reading, the cuvette is not clean.

Any bubbles in the sample will affect the readings. Take care not to introduce bubbles
into samples. Remove any bubbles by lightly tapping with your finger on the outside
cuvette wall or cover the top of the cuvette and tilt the sample to help dissipate bubbles.
4.2 Positioning Samples
The orientation of the cuvette in the sample compartment can give slightly different readings
especially for low concentration samples. This is due to variations in the walls of the cuvette
that are not readily visible to the eye. We recommend that the cuvette be marked at the top
on one side and positioned in the sample compartment the same way each time for best
results.
Turbidity sample measurements are particularly sensitive to the quality and cleanliness of
the cuvette. Small scratches or smudges on the cuvette will affect the accuracy of the
readings. The Polystyrene cuvettes (P/N 7000-957) give the best Turbidity measurement
results, due to better quality of the cuvette.
4.3 Data Quality
The Aqua Fluor
®
is only as accurate as the standards that are used to calibrate it. This is
why it is important to take care when preparing standards, samples and blank. One should
follow good laboratory practices when preparing all solutions and samples.
The best results are obtained if you determine the range you anticipate your samples are
going fall in and calibrate to optimize resolution. If a low concentration calibration standard
is used then the low end of the linear range will have better resolution. If a high
concentration calibration standard is used the high end of the linear range will have better
resolution.