Zinc(II) complexation by some biologically relevant pH buffers

Abstract

The isothermal titration calorimetry (ITC) technique supported by potentiometric titration data was used to study the interaction of zinc ions with pH buffer substances, namely 2-(N-morpholino)ethanesulfonic acid (Mes), piperazine-N,N'-bis(2-ethanesulfonic acid) (Pipes), and dimethylarsenic acid (Caco). The displacement ITC titration method with nitrilotriacetic acid as a strong, competitive ligand was applied to determine conditional-independent thermodynamic parameters for the binding of Zn(II) to Mes, Pipes, and Caco. Furthermore, the relationship between the proposed coordination mode of the buffers and the binding enthalpy has been discussed.

Characterization and cytotoxic effect of aqua-(2,2′,2′′-nitrilotriacetato)-oxo-vanadium salts on human osteosarcoma cells

“…Potentiometric titrations were performed at 298.15 K by using Cerko Lab System microtitration unit fitted with 5‐mL Hamilton’s syringe and pH‐combined electrode (Schott‐BlueLine 16 pH type) All details for the measuring devices and the experimental setup were described in (Wyrzykowski et al 2014). The ionic strength was maintained at 0.1 M using NaClO 4 .…”

Probing the binding selected metal ions and biologically active substances to the antimicrobial peptide LL-37 using DSC, ITC measurements and calculations

“…A different situation is observed for zinc ions where the Mes buffer component (a conjugate base) competes with the LL-37 peptide for the Zn 2? ion [34]. For these reasons, the heat effects that are not connected directly with the peptide-metal interaction (e.g., metal-buffer interaction) affect the obtained thermodynamic parameters.…”

Aquation reaction of iminodiacetate complex of oxidovanadium(IV) with 2,2’-bipyridine induced by Fe(III) ions: Kinetic studies

“…The substitution reaction of complex compounds with special promoters may occur in acidic (the promoters are H + ions) or basic (the promoters are OHions) media or may be induced with Fe 3+ ions. [1][2][3][4][5][6][7][8] Polycarboxylic anions are a group of organic compounds which are used in coordination chemistry as ligands, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] because they stabilize metal ions in solutions 14 and, moreover, they are noncytotoxic. 15 Furthermore, the polycarboxylate coordination compounds of cobalt(II), nickel(II), 12,16,18 oxidovanadium(IV), 15,17 and copper(II) 19,20 have interesting antioxidant, antibacterial, and antifungal activities.…”