This might sound silly, but I would use whatever method has the most local expertise in your institute.  When I was making yeast extract, I read a review that actually showed data on variation in effectiveness of different homogenizers (same type/manufacturer - just different individual homogenizers!).  If there is one around that is proven to be effective, then use it.  I ended up using a mortar and pestel with liquid nitrogen for freeze fracture - for that I really needed someone with experience to direct me on how to do it properly and when it was done.  I think the most important thing is that you can do this as quickly and efficiently as possible.

Homogenizer is always better than the manual mortar and pestle. Although not viral RNA, but I have extracted bacterial DNA from digesta and RNA from single cell cultures and tissue explants using homogenizer with RIN values around 8.5 to 9.5 !

Dear Amanda,

It is always easy to say silly, but loss of RNA does matters.... After all this question is for virologist.

Thanks...

Hi,

I think that most important is temperature and resuspension buffer compositions. Both are related to do not allow that endogenous RNAses works. More crucial is if you add liquid nitrogen during homogenization that the way or instrument that you use. About lysis or resuspension buffer of your powder or homogenate, as much denaturing your resuspension buffers are, such as guanidine thiocyanate, you are avoiding that RNAses work....and of course as fast as you can always is better to avoid RNA degradation...I hope it helps

I don't know if this is a possibility for you but we routinely use a modified drill to grind frozen plant leaf tissue (tubes are kept in liquid N until grinding).  We had drill attachments made to fit into 1.5 and 2ml tubes.  This works really well for our samples and you don't lose any material as it is all contained in the tube.  We have also used this method for extracting high quantities of very clean RNA from insects.

Dear Andrew,

Thanks for your reply..