In article <[email protected]>, [email protected] says... > > Hi, > > I was wondering that will radioactivity incorporation amount remain > constant in a pcr reaction over 1 or two half lives? > > The basis being that P32 decays into S32 with time, and the question is > whether this S32-dNTP will be a substrate for PCR? Because if it is not, > can you keep on adding more hot dNTP (to an extent) and freshly prepared > probes will be equally hot even after say one or two half lives? > > so is it Ok to use aP32 labelled probes uptill few half lives of the dntp > as long as you are freshly preparing them and compensating amounts in PCR > for decay? > > thanks in advance. > > Vishal
There are two main problems with "old" radioactive probes: - the amount of probe gets reduced by radioactive decay, this cannot be affected - radiolytic destruction. This can be minimized by low temperature (which is why samples are usually frozen at -80 °C, even if the parent compound is stable in the fridge) and by some additives like antioxidants. However, I'd be very careful about using radiochemicals after more than 2-3 halflifes. -- Car (noun): erratically moving obstacle on the road _______________________________________________ Methods mailing list [email protected] http://www.bio.net/biomail/listinfo/methods
