Cell lysate turbidity upon long storage - (Dec/04/2011 )

Dear Friends

Iam working on mammalian cell lines to study their apoptosis, for that iam treating cells (5million roughly)with drugs to induce apoptosis later using Mper to lyse the cells.these cell lysate stored at -20oC.after a week or so i started observing tubidity in samples.why? where is the problem.people suggest me what should i do .

Thanks

What is in the lysis buffer, and did you spin out the insoluble bits before storage?

Bob sorry for delay

Mper Invitrogen is the lysis buffer i used and in that protease inhibitor sigma added. before storage i spun samples at 13,000RPM for 10mins.

I think you will find that it is due to the samples re-suspending fine particles during the freeze/thaw process. Re-spin your samples as you did before freezing, and the samples should be clear again.