Particulate Systems NanoPlus, Operator'S Manual, Page: 207 / 252

NanoPlus Operator’s Manual ACF (Base)
Mar 2014 D-15
ACF (Base)
The Electrophoretic Mobility of the sample is determined by using heterodyne type of
measurement. The measurement requires a reference signal; the Base, whose frequency is
compared with the scattered laser light frequency from the sample; and the Doppler Shift
(modulator signal) is calculated.
The Base frequency is dependent on the type of cell used and the concentration of the sample.
Typically, for the flow cell and Flat Surface cell, the Base frequency varies between 120-140 Hz,
and for the High Concentration cell, the Base frequency varies between 220-270 Hz.
If the cell center is not appropriate, you may not get a good ACF for Base measurement. In that
case, the cell center of the cell can be detected before carrying out the analysis.