Capability of arsonolipids to transport divalent cations: A Pressman cell study

Abstract

The ability of the newly synthesized arsonolipids (2,3-diacyloxyprophlarsonic acids) to transport cations was studied using the Pressman cell. Experimental results demonstrate that arsonolipids are much more efficient carriers of Ca2+ and Mg2+ than natural phosphatidic acid in the Pressman cell experiments. The ability of arsonolipids to transfer Ca2+ is affected by the lipid side chain length in the order: C12≫C14≅C16. Ca2+ is transferred faster than Mg2+, suggesting that the latter is more tightly bound to the arsonolipids. The transfer kinetic curves are parabolic for C12, while initially linear with a tendency to reach a steady state for C14 and C16, when the pH in the donor compartment was 8.3. The transport kinetics for both ions studied were best fitted by an equation derived from saturation kinetics that apply in reversible chemical reactions. The ion transfer rates increased as the pH in the donor compartment decreased. © 2001 Elsevier Science Ireland Ltd. All rights reserved.