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preference. In aqueous solution, the dye has excitation/emission maxima of 493/636 nm. When bound,
the excitation/emission maxima shifts to 535/617 nm respectively.
Calculation:
% Viability =(Brightfield count / (Brightfield count+ PI count)) *100.
AO/PI App
The AO/PI App uses green fluorescent images to capture live nucleated cell counts and red fluorescent
images for counting dead cells.
Acridine orange (AO) and propidium iodine (PI) are both cell permeable nuclear dyes that in combination
are used to count live and dead cells within a cell solution. The AO enters both live and dead cells and
results in green fluorescing cells. PI enters only nucleated cells with compromised membranes to
generate red fluorescence. Cells stained with both AO and PI fluoresce red due to fluorescence
resonance energy transfer (FRET).
% Viability =(AO count / (AO count+ PI count)) *100
GFP App
The GFP App uses green fluorescent images to count GFP transfected cells and brightfield images to
count non-transfected cells
The green fluorescent protein (GFP) isolated from the
Aequorea victoria
jellyfish is a useful
reporter molecule for monitoring gene expression. GFP emits green light (lambda max = 509 nm) when
excited with UV or blue light resulting in cells that green fluorescent cells.
The GFP app is used to determine the transfection efficiency of transient transfections.
% Efficiency =(GFP+ count / (GFP+ count+ Brightfield count)) *100
Yeast App
The Yeast App uses green fluorescent images to capture live yeast cell counts and red fluorescent
images for counting dead yeast cells.
Yeast cell live/dead staining can be done using Fluorescein diacetate (FDA) and Propidium iodide (PI).
FDA freely moves in and out of the plasma membrane of diverse organisms from bacteria to mammalian
cells. The non-fluorescent FDA taken up by cells is converted the into the green fluorescent metabolite
fluorescein. The green fluorescence is used as an indicator of live cells. PI enters only nucleated cells
with compromised membranes to generate red fluorescence indicating dead cells.
Note: Yeast cells are smaller than typical mammalian cells and may take a little longer to settle into
position.
% Viability =(FDA count / (FDA count+ PI count)) *100
Summary of Contents for CellDrop
Page 1: ...rev MAR 27 2019 ...
