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Introduction
1.2.3 Measuring Range Dynamics
The signal amplifier technology, developed specifically for the CASY Cell Counter and Analyzers,
guarantees excellent measuring range dynamics (>1:70,000 in terms of volume and >1:40 in terms
of diameter respectively).
Measuring range dynamics is described as the ratio of the smallest to the largest particles that can
be analyzed simultaneously. This guarantees that the entire physical measuring range of the mea-
suring capillaries used, from approximately 2% to approximately 80% of the measuring pore diam-
eter, is always in view. As an example, the entire physical measuring range of the 150 μm capillary
ranges from 3.2 μm (2% of 150 μm) to 120 μm (80% of 150 μm).
Due to the huge dynamic measuring range with 1:40, in terms of the diameter offered by the
CASY Cell Counter and Analyzer, objects with a size of 3.2 μm and approximately 40-times
bigger objects, for example, objects with a size of 120 μm, can be measured in one measurement
using the 150 µm capillary. When analyzing cell cultures, this means that you can analyze everything
from very small debris particles up to very large cell aggregates simultaneously.
Figure 3
below shows
a typical size distribution of an animal cell line generated by the CASY Cell Counter and Analyzer.
Based on the precisely determined cell volumes, the CASY Cell Counter and Analyzer calculates the
corresponding cell diameters, which are displayed together with their associated absolute counts,
resulting in the typical high-resolution size distribution:
Figure 3: Typical CASY Cell Counter and Analyzer size distribution on an animal cell line
Capillary Sizes
In order to cover different size ranges for specific applications, capillaries with different pore sizes
are available covering different measuring ranges. In addition to the 150 μm capillary, the 45 μm
capillary (pore size 45 μm) and the 60 μm capillary (pore size 60 μm) are offered.
A CASY TT can be equipped with either the 150 μm capillary only or with all three capillaries (150
μm, 60 μm and 45 μm). The 45 μm capillary detects objects starting from 0.7 μm and therefore is
used, for example, to analyze bacteria or small fungi, whereas the 60 μm capillary detects objects
starting from 1.2 μm and is used, for example, for analyzing yeast cells, platelets, sperms, algae,
plankton, etc.
Based on the measurement principle and different available capillary sizes, a broad range of objects
can be quantified by the CASY Cell Counter and Analyzer, as for example, all types of mammalian
cells (cell lines and primary cultures), blood cells, algae cells, yeast cells, bacteria, sperm, pollen,
worm eggs, particles, etc.
Measuring Principle
Measuring Range Dynamics
