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The XL system features the capability
to analyze up to 4 colors of immunofluorescence from a single air
cooled laser. Other multi-color applications include:
multiparametric DNA analysis, platelet studies, reticulocyte
enumeration, cell biology/functional studies and as well as a broad
range of research applications. The instrument is self contained and
biohazard safe. The user retains the flexibility to change filter
elements for versatility in research settings.
So what can I do
with my EPICS XL ???
A cell may be
analyzed by its individual characteristics. The “intrinsic”
characteristics are investigated without reagents. The
“extrinsic” characteristics are investigated by the use of
reagents (such as fluorescent antibodies).
Intrinsic Structural Characteristics
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Cell size
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Cytoplasmic granularity
Extrinsic Functional Characteristics
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Enzyme activities
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Apoptosis
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Cell Surface markers
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Intracellular receptors
- DNA
synthesis
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Membrane fluidity and viscosity
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Cytoplasmic/mitochondrial membrane potential
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Membrane bound Ca++ ions
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Cytoplasmic Ca++ ions
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Intracellular pH
The
COULTER EPICS XL-MCL is a laser-based flow cytometer
which utilizes color-differentiated fluorescence and
light scatter measurements to analyze cells. Cells in
liquid suspension are presented under pressure to a flow
cell where they are surrounded by a laminar sheath of
particle-free liquid. This coaxial stream passes through
a flow chamber as a jet. Cells are presented one at a
time to a laser beam generated by a 488 nm argon laser.
The instrument can handle up to 10,000 cells per second.
As the cells pass through the laser beam they will (1)
scatter light and/or (2) fluoresce, due to either
autofluorescence or to the presence of fluorescent
stains which have been selectively absorbed or bound by
the cell. The scatter and fluorescence emissions are
collected by detectors (photo diodes and photomultiplier
tubes) which convert the signals to voltage pulses that
are proportional to the amount of light scattered and/or
to the intensity of the fluorescence. These pulses are
then amplified and converted to a digital form which can
be displayed in numeric and/or histogram formats. This
instrument has four PMT’s allowing an investigator to
look at four colors of fluorescence at once. |
For high volume users, the XL-MCL
system offers walk away sample handling for superior efficiency with
the Multi Carousel Loader (MCL). Capable of throughputs of up to 100
samples per hour, the fully featured XL-MCL incorporates positive
bar-code identification and true vortex mixing prior to aspiration.
The XL remains the only flow cytometer
to offer state-of-the-art Digital Signal Processing (DSP) for reliable
linearity and drift-free amplification and compensation. The single
laser design eliminates concerns regarding multi-beam stability,
signal delay and alignment. Compensation is achieved by a unique
digital compensation matrix.
Flow Cytometry: A new Dimension
in Disease Diagnosis and Management.
Flow cytometry is the most practiced member of a family of
technologies known variously as automated, analytical, or
quantitative cytology. As the term implies, flow Cytometery is the
measurement (-metry) of cellular (cyto-) properties as they are
moving in a fluid stream (flow), past a stationary set of
detectors. Flow cytometry is the only technique capable of
quantitative measurements of multiple features of individual cells
in a rapid manner.
Flow cytometry is a means of measuring certain physical and
chemical characteristics of cells or particles as they travel in
suspension one by one past a sensing point. In one way, flow
cytometers can be considered to be specialized fluorescence
microscopes. One could measure physical characteristics such as
cell size, shape and internal complexity and, of course, any cell
component or function that can be detected by a fluorescent
compound can be examined.
It is a rapid method for measuring the fluorescence and light
scattering of individual cells in large numbers. By labeling the
cells with fluorescent molecules that bind with high specificity
to one particular cellular constituent, it is possible to measure
the contents of the constituent. Such a fluorescent tag may be
either a dye molecule with a high binding-specificity for the
particular component to be measured or a fluorescence-conjugated
antibody. The light scattering of the cells gives information on
their size and to some extent also on shape and structure.
This marvelous technical accomplishment is a convergence of
computer science, laser development, electronics, hydrodynamic
focusing and ink-jet technology, optics and light detection,
monoclonal antibodies, and DNA analysis. The flow cytometer is
capable of rapid, quantitative, multiparameter analysis of
heterogeneous cell populations on a cell-by-cell basis (single
cell analysis).
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