In vitro experiments and infrared spectroscopy analysis of acid and alkaline phosphatase inhibition by vanadium complexes

Abstract

In the course of our research on vanadium-containing complexes, two oxidovanadium complexes containing vanadium(V) and (IV) cores with 4-aminobenzoic acid and/or the peroxo anion as ligands were synthesized and characterized by elemental analysis, conductivity measurements, thermogravimetric analysis, and ¹H NMR, EPR, FTIR, and UV/vis spectroscopies. Their compositions and geometrical structures ([VO(O₂)(C₇H₆NO₂)(H₂O)]·H₂O and [VO(C₇H₆NO₂)₂H₂O]) were supported by experimental data and theoretical studies (density functional theory, DFT). The complexes were evaluated in vitro as phosphatase inhibitors (alkaline and acid enzymes), being considered as potential pharmaceutical agents under over-expression of those biochemical markers. The effect achieved was then analysed through FTIR spectroscopy. Changes in the fingerprint substrate bands as well as induced conformational changes in phosphatase enzymes’ secondary structure were further examined. Eventually albumin interaction experiments were performed in order to derive their bioavailability.