Spectrofluorometric studies on the binding of the antitumor drugs ametantrone and mitoxantrone to bovine serum albumin.

Mitoxantrone binds tightly to one high affinity site, while ametantrone was found to bind to at least two different sites. The two compounds were able to displace the fluorescent probe 7,12-dimethylbenzanthracene from its hydrophobic site on the bovine serum albumin molecule, but at high ametantrone concentration, no further displacement was noticed, which may indicate that at concentrations higher than 50 microM conformational changes in the protein molecule may be caused by ametantrone.