what is the purpose of the alkaline solution(the one on which you place the sponge then the gel) in southern blot, ie why is it not acidic or something else other than alkaline ??
If alkaline transfer methods are used, the DNA gel is placed into an alkaline solution (typically containing sodium hydroxide) to denature the double-stranded DNA. The denaturation in an alkaline environment provides for improved binding of the negatively charged DNA to a positively charged membrane, separates it into single DNA strands for later hybridization to the probe (see below), and destroys any residual RNA that may still be present in the DNA.
another question, however, the radioactive single stranded DNA (probe) is extracted from the person/suspect that we are trying to match his DNA to the DNA that we got from the crime scene and used in the experiment, correct?
