Chemical speciation, antioxidant activity and molecular docking of copper(II) complexes with pyridinedicarboxylic acids and different ligands of low molecular mass

Analyses of potentiometric measurements were conducted on ternary complexes of copper(II) with dipicolinic acid and quinolinic acid, as well as lactic acid, oxalic acid, citric acid, and phosphoric acid, which are components of blood plasma. Studies on chemical speciation showed that ternary compounds were more likely to be formed. In systems with quinolinic acid, the solubility was small, and most complexes precipitated at pH <= 2. In situ isolated ternary and binary complexes of CuDiPic(H2O)(2) were evaluated for antioxidant activity, as shown by their inhibiting activity of superoxide anion (O-2.(-)), which demonstrates copper(II) complexes provide protective effects. Docking studies of ligands with a protein kinase revealed that the Cu(II) metal centre is crucial for the successful interaction of the complex with the receptor's active site.

Automated summary

In this study, potentiometric measurements were conducted on ternary complexes of copper(II) with various components of blood plasma, revealing their speciation and antioxidant activity. Docking studies further demonstrated the crucial role of the Cu(II) metal centre in the interaction with the receptor.