Try the following:
OD550 = (1.0315e-8)(cell number/ml)+1.7633e-3
The r-squared for this regression is 0.9997 and the data are for the
genus Vibrio (taken from Primrose & Wardlaw, 1982, Sourcebook of
experiments for the teaching of microbiology, p. 151). This equation is
valid only for ODs from 0.02 to 0.50, and in general one should be use
ODs less than 1 for accuracy (so dilute).
Wayne A Sargent (wsargent at badlands.NoDak.edu) wrote:
: I would truly appreciate a formula for converting an OD reading
: into an approximate # of bacterial cells/ml.
: THANX in ADVANCE!
: ------------------------------------------------------------------------------
: Wayne Sargent
: Department of Plant Sciences
: Loftsgard Hall, Room 166 phone : 701-231-8057
: North Dakota Sate University fax : 701-231-8474
: Fargo, ND 58105 e-mail: wsargent at badlands.NoDak.edu
: ------------------------------------------------------------------------------
--
===================================================================
Scott T. Kellogg, Dept. of Microbiol., Mol. Biol. & Biochem.
Univ. of Idaho, Moscow, ID 83844-3052 Internet: kellogg at uidaho.edu
Phone: 208-885-6966 Fax: 208-885-6518
