Dead cell exclusion – in a “virtual” flow cytometry channel

DRAQ7-labeled dead cells can be excluded without any need for a separate channel or compensation!


HOW? 
DRAQ7 can be excited across the visible spectrum, from blue to red.
No other chromophore we have checked behaves like this.  And, it’s easy:

• Split a sample. Stain half with antibody panel alone and half with antibody panel + DRAQ7  
• Analyse each on a flow cytometer with at least two lasers (from blue to red)
• Plot all the red and far-red channels against each other
• Choose a bi-exponential plot with clearly separated double-positive events (in +DRAQ7 tube)
• These are the DRAQ7+ dead cells – draw a gate to exclude them
• You’ve now set up your virtual channel for dead cells with this panel!

RESULT:
The dead cells disappear from all channels, requiring no compensation or adjustment of voltages, panel splitting or transfer to a more complex instrument.  Just imagine, now you can take an existing panel and add the viability dye DRAQ7! You can even make a 6 channel instrument accept 7 colours!

Depending on your flow cytometer’s laser and detection channel choices you can easily set up a panel that works like this with blue, green, yellow, orange, or red lasers!  All you need is two of these lasers and you are away!

Get a copy of our application note or the poster (Abstr. 144) from CYTO 2014 via the contact page

Another reason why DRAQ7 is THE viability dye of choice!     #DRAQ7