Reatividade de complexos [RuIICl(X−tpy)(BDQ)]+ (X=Cl OU H): aspectos na cinética de aquação e interação com albumina humana

Abstract

Cancer is a disease that consists of uncontrolled cell growth. These cells can invade tissues and / or organs in a process called metastasis. However, the demand for drugs that act as antitumor drugs is vast. Many coordination compounds that have a metallic ruthenium (II) center with polypyridine ligands, show promising anti-tumor agents. The ruthenium (II) complexes offered perspectives, an oxidation states stable under physiological conditions, solubility in water and less toxicity when compared to conventional platinum (II) drugs. This work described the synthesis, characterization, determination of the aquation kinetics and interaction with human albumin of complexes of the type [RuIICl (X − tpy) (BDQ)] (PF6) (X = H or Cl), denominated from [Ru(tpy)] and [Ru(Cl-tpy)]. Both the [Ru(tpy)] and [Ru(Cl-tpy)] complexes, after synthesis, present position isomers verified through HPLC analysis. The results obtained through the study of aquation kinetics, in turn, demonstrated that both studied complexes have constant aquation kinetics with an order of magnitude greater than the cis-diaminodichloridoplatin (II) complex. When analyzing the results of suppression of fluorescence, it was verified the presence of interaction between the [Ru(tpy)] and [Ru(Cl-tpy)] complexes with human albumin (HSA). However, when observing the Ka values, it was noted that the interaction is weak. Synchronous fluorescence suppression experiments and it was observed that only [Ru(tpy)] is able to alter the protein microenvironment close to an amino acid residue, Trp-214.