Worm Breeder's Gazette 6(1): 37b

These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.

Modified Ficoll Method for Cleaning Worms

J. Lewis

I have made two modifications in the Ficoll method I originally 
described in WBG, vol. 3, #2.  First, all Ficoll solutions are made 0.
1 M in NaCl to avoid shocking osmoticalIy sensitive worms like unc-29(
e1072).  Second, after sedimenting worms through 15% w/w Ficoll 400 (
15', 300 x g), the worms are diluted with an equal volume of 0.1 M 
NaCl and floated on 35% w/w Ficoll (15', 300 x g) before washing 2x 
with 0.1 M NaCl.  The Ficoll sedimentation removes dead or degenerated 
worms, cuticles, bacteria.  The flotation removes crystalline debris 
sometimes occurring in worm cultures.  We also find that special care 
to pipette out the last residue of bacterial medium (e.g.  3XD) before 
resuspending bacteria for worm growth is most conducive to obtaining 
uncontaminated worms.