Survey of the DNA binding properties of natural and synthetic polyamino compounds

Using a flourescence‐detected ethidium displacement assay, the calf thymus DNA complexation properties of 27 mono‐, di‐, tri‐, tetra‐ and hexacationic polyamines were determined. The DNA‐binding affinity of these polyamine compounds increased with increasing cationic charge on the polyamine. Although most of the compounds exhibited no base pair binding selectivity, two of the tricationic polyamines possessing additional neutral amine groups exhibited approximately tenfold GC binding selectivities.