Malvern Zetasizer Nano Series, Accessories Manual

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Chapter 5 Microrheology
Page 5-14 MAN 0487

The tracer size measurement is used later in the microrheology measurement
step. The tracer size needs to be measured to ensure the microrheology result
is as accurate as possible.

When finished a dialogue will appear indicating the next step to perform.
Measure tracer zeta potential in dispersant/buffer (or solvent) including
sample
This is termed the sample measurement.
Use a zeta potential cell.

Prepare the sample to be used for the measurement, then add small amount of
tracer particles - do this at a concentration similar to that used in the previous
step.

Ensure the tracer and measurement sample are mixed.

A measurement of the zeta potential of the tracer in the measurement sample is
then performed.

Once this measurement is complete the software compares the two measured
zeta potential results and tests to see if
sample
measurement is within a set
percentage of the
tracer
measurement - this is the
acceptable zeta ratio
.
If the ratio is
less than 25%
the measurement process will continue to the next
step otherwise with a dialogue appearing indicating the next step to perform.
If the ratio is
more than 25%
the software will give sample preparation advice
and advise on repeating steps 1 and 2. Refer to the
zeta potential - accepta-
ble zeta ratio
section.