Investigation on sonocatalytic damage of BSA under ultrasonic irradiation by FeIII complexes with some aminocarboxylic acid

Abstract

The interaction of BSA and FeIII complexes ([FeIII(gly)(H2O)4]2+, [FeIII(ida)(H2O)3]+, and [FeIII(nta)(H2O)2], gly—glyane, ida—iminodiacetic acid, nta—triglycolamic acid) as well as the sonocatalytic damage to BSA was studied by UV-vis and fluorescence spectra. In addition, the influences of ultrasonic irradiation time and FeIII complex concentration were also examined on the sonocatalytic damage to BSA. The results showed that the fluorescence quenching of BSA solution caused by the FeIII complexes belonged to the static quenching process. The BSA and FeIII complexes interacted with each other mainly through weak interaction and coordinate actions. The binding association constants (K) and binding site numbers (n) were calculated. The results were as follows: K1 = 0.5353 × 104 l mol−1 and n1 = 0.9812 for [FeIII(gly)(H2O)4]2+, K2 = 1.4285 × 104 l mol−1 and n2 = 1.0899 for [FeIII(ida)(H2O)3, and K3 = 0.4411 × 104 l mol−1 and n3 = 0.9471 for [FeIII(nta)(H2O)2]. Otherwise, under ultrasonic irradiation the BSA were obviously damaged by the FeIII complexes. The damage degree rose up with the increase of ultrasonic irradiation time and FeIII complex concentration. And that, [FeIII(nta)(H2O)2] exhibited in a way higher sonocatalytic activity than [FeIII(gly)(H2O)4]2+ and [FeIII(ida)(H2O)3]+.