Chapter 6
Advanced protein features
Page 6-2
MAN 0487
6
The basic steps involved in a measurement are:
The first step is the
thermal
equilibration
delay
, performed in order for the
sample and cell to properly equilibrate with the Zetasizer cell holder.
An optional
pre
-mobility
size
measurement is completed so that the user can
check that the sample is not aggregated.
This result is recorded into the protein mobility parent record as a child record
of type
size
.
A
zeta potential
measurement follows for measuring the mobility.
A normal zeta potential measurement consists of a number of sub-runs, at the
end of which the final result (the average over all recorded sub runs) is
reported into the record view.
During the measurement proper, running a large number of sub-runs
sequentially will significantly increase the risk of Joule heating of the sample. to
prevent this the protein mobility measurement is split into the smaller
groups
of sub-runs with a delay added between each group to allow the sample to
relax.
ill ill8801
Once the measurement starts the
Expert
system will check and warn if the
sample has will be subject to levels of Joule heating or Polarisation/field
estimation issues that might affect the measurement accuracy. Appropriate
advice is given, for such cases, on the
Expert advice tab
on the
live display
and after the measurement on the record view.
t=0
Thermal Delay
Pre-Size
Delay
Delay
Post-Size
Aggregate, joule heating
and polarization
concentration detection
during each group
}
