loss of cytotoxicity - (Mar/20/2007 )

compound lost its cytotoxicity all of a sudden

The compound I was working on suddenly lost its cytotoxicity. It is my PhD work, I have about one year's work, but it is not enough. I changed to fresh cell lines, weighed, made fresh aliquots of the compound, made fresh medium, am still to try it out with fresh batch of serum. All of a sudden it stopped showing its cytotoxicity. Cant just point to anything speciifc. Does antimycotic antibiotic solutions have such an effect. I am frustrated and desperate.

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changing "to fresh cell lines" menas these cells had never contact to your toxin before, right? so, it is not a kind of resistance;

there are two likely possibilities: either your stock compound degraded (f.i. oxidation) or you changed your protocol to test cytotoxicity which blocked cytotoxic effect; antimycotics may stimulate detoxification processes in the cell; why is there any need to use antmycotics? working truely sterile does not need antiobiotics or antimycotics

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