DAPI question

[Oivind Enger]

Here comes the DAPI protocol that we usualy apply on bacteria:

1) Prepare a 1 mg/ml stock solution of DAPI and freeze in aliquots
2) Dilute the stock 1/100 in dH2O
3) Preserve cells to be counted with 2% (final conc.) formaldehyde. (for at 
   least 4 hours).
4) Filter cells onto black Nuclepore membrane filters with pore size 0,2 um
   (You can buy them black or stain them yourself with Irgalan Black)
5) Cover membrane with DAPI soultion (use syringe and syruinge tip filter)
6) Incubate for 5 min
7) Wash filter with 5 ml (0,2 um filtered) dH2O
8) Mount in liquid paraffin in microscope slide
9) View in epifluorescence microscope under UV exitation

Good luck!

-oivind enger