Biochemistry 4th Edition by Reginald Garrett, Charles Grisham

Exercise 11

Calculating Tms and separating DNA molecules that differ in G:C content
At 0.2 M Na+ the melting temperature of double-stranded DNA is given by the formula Tm = 69.3 = 0.41(%G + C). The DNAs from mice and rats have (G + C) contents of 44% and 40%, respectively. Calculate the Tms for these DNAs in 0.2 M NaCl. If samples of these DNAs were inadvertently mixed, how might they be repurified from one another