Hi all,

Just have a quick question: How does one do a physical viral titer count (particles/mL)? Is it by OD280? Anyone have a protocol?

Thanks very much in advance.

The second result here has many references for performing actual viral particle counts.

Question: Are you trying to titer a virus that has a known host in culture. If so you can use the plaque assay to determine your titer (here is a method for the plaque assay : http://www.virusecology.org/MOVE/Method%208.html). If your virus does not have a host or if you are just doing total virus counts you can use microscopy (Noble, R.T. and Fuhrman, J.A. 1998. Use of SYBR Green I for rapid epifluoresence counts of marine viruses and bacteria).