Moxi V
™
User Guide
Page 37
down for the size histogram and left-right for the fluorescent histogram. The image below/right
shows the effect of making broad left-to-right swipes as well as top-to-bottom swipes in the
scatter plot region of the middle image below. The result is that the fluorescence histogram
scale is decreased (increasing histogram height) and the size histogram scale is increased
(shrinking the size histogram).
“Size Histogram” Assay
For samples that lack any staining or fluorescent label, quick counts and particle sizing
information can be obtained by running a “Size Histogram” assay. As the laser is not used with
this assay, time is saved as the system skips the laser/cassette alignment step. Size-only tests
can be run by selecting “Cell Counts (Size Only)” assay. During acquisition a size-based
histogram is displayed as opposed to the traditional fluorescence vs. size scatter (dot) plot.
Upon completion of the test, counts for the “Size histogram” can be obtained by moving the blue
gating markers to define the size region for the counts (image below/middle). For monodisperse
cell populations, the system can also be set to curve-fit the data automatically. When curve-
fitting, the system looks to find the core, singlet Gaussian population. That population is curve-
fit automatically. The system uses the mean of the Gaussian to determine (and report) the
singlet cell size/volume (black box in the bottom right).
For smaller particle populations, improved size resolution can be achieved by rescaling the x-
axis (as discussing in the above “Rescaling the X-axis” section) to 2-17 µm or 2-9 µm.
Rescaling doesn’t just show a subset of the currently displayed histogram. Rather, system
reprocesses the raw data wave to generate a 1000 bin histogram across the smaller size range,
thereby improving the resolution.
Swip
