Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published January 11, 2000 | public
Journal Article

pH-Induced Fusion and Lysis of Phosphatidylcholine Vesicles by the Hydrophobic Polyelectrolyte Poly(2-ethylacrylic Acid)

Abstract

Poly(2-ethylacrylic acid) [PEAA] was shown to induce fusion of phosphatidylcholine bilayer membranes under mildly acidic conditions. The pH-dependent destabilization and fusion of extruded large unilamellar vesicles (LUVs) by PEAA was characterized by optical density measurements, transmission electron microscopy, and lipid-mixing and contents-release assays. Reduction of either the chain length or the polymer concentration caused the fusion and contents-release events to shift to lower pH values. Release of entrapped calcein was observed at pH values approximately 1 unit higher than those found to cause membrane fusion. Decreased levels of fusion were observed when the concentration of PEAA was lower than that of the lipid; however, quantitative release of encapsulated calcein could be effected at very low polymer concentrations (∼3% w/w PEAA/lipid).

Additional Information

Copyright © 2000 American Chemical Society. Received May 24, 1999. Publication Date (Web): December 10, 1999. The authors thank Howard Bowman, Wendy Naimark, Jan van Hest, and James Thomas for helpful discussions, as well as David Flanagan for review of this manuscript and discussions. This work was supported by a grant from INEX Pharmaceuticals, Inc. Part of the Special Issue "Clifford A. Bunton: From Reaction Mechanisms to Association Colloids; Crucial Contributions to Physical Organic Chemistry". This paper is dedicated to Professor Clifford A. Bunton on the occasion of his eightieth birthday.

Additional details

Created:
August 19, 2023
Modified:
October 19, 2023