softscience

CharonY, Thanks! Do you think that aliquots of 500ul would be a problem? As I understand it you want to reduce the amount of time during freeze/thaw to prevent compromising activity? Thanks!

I'm running an assay that calls for use of trypsin to cleave a fluorescent peptide reporter, and the protocol specifies that trypsin (lipholized) should be aliquoted out at 300X working concentration and frozen at -80 for storage. The protocol does not include a resuspension buffer. My question is, is it ok to just use DI water to reconstitute the solid trypsin that I have and then freeze at -80? Most of the literature says that trypsin life can be lengthened by first dropping the solution pH with either 1mM HCl or 50mM acetic acid to reversibly inactivate the trypsin so it doesn't autolyse itself during storage at 4 or -20. I can't find anything about -80 storage however. Is the activity sufficiently curbed at this temperature that acid does not need to be added to prevent autolysis during storage? I don't want to introduce extra acid to one of my assay components if I don't need to. Thanks!