Spectroscopic investigation on the sonodynamic activity of amsacrine (AMSA) to bovine serum albumin (BSA) damage

The sonodynamic damage of bovine serum albumin (BSA) under ultrasonic irradiation in the presence of amsacrine (AMSA) was studied by hyperchromic effect of UV–vis spectra and quenching effect of intrinsic fluorescence. In addition, several influencing factors such as ultrasonic irradiation time, AMSA concentration, system acidity and ionic strength about the damage of BSA molecules were reviewed. The results showed that the damage degree was obviously enhanced with the increase of ultrasonic irradiation time and AMSA concentration, but it was only slightly increased with the increase of solution pH value and ionic strength. Furthermore, the binding and damaging sites to BSA molecules were estimated by synchronous fluorescence spectra. The different chances to damage tryptophan (Trp) and tyrosine (Tyr) residues were found through the ratios of synchronous fluorescence quenching (RSFQ). At last, the generation of reactive oxygen species (ROS) in sonodynamic process was estimated by the method of oxidation-extraction Spectrometry (OES). And then, several radical scavengers were used to determine the kind of ROS, which includes singlet oxygen (1O2) and hydroxyl radicals (·OH). Perhaps, the result would bring a certain guiding significance to use sonosensitive drugs in the fields of tumor treatment.