Permeabilization of Lipid Membranes and Cells by a Light-Responsive Copolymer

• Published in: Langmuir 2010-09, Vol.26 (17), p.14135-14141
• Main Authors: Sebai, Sarra C, Cribier, Sophie, Karimi, Ali, Massotte, Dominique, Tribet, Christophe
• Format: Article
• Language: English
• Subjects: Acrylic Resins - chemical synthesis; Acrylic Resins - chemistry; Animals; Azo Compounds - chemistry; Biological Interfaces: Biocolloids, Biomolecular and Biomimetic Materials; Cell Membrane Permeability; Cell Survival; Cells, Cultured; Cercopithecus aethiops; Chemical Sciences; Chemistry; Colloidal state and disperse state; COS Cells; Exact sciences and technology; General and physical chemistry; Hydrogen-Ion Concentration; Hydrophobic and Hydrophilic Interactions; Light; Membrane Lipids - chemistry; Membranes; Molecular Structure; Organic chemistry; Osmolar Concentration; Surface Properties
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la102456z

Membrane permeabilization is achieved via numerous techniques involving the use of molecular agents such as peptides used in antimicrobial therapy. Although high efficiency is reached, the permeabilization mechanism remains global with a noticeable lack of control. To achieve localized control and more gradual increase in membrane perturbation, we have developed hydrophobically modified poly(acrylic acid) amphiphilic copolymers with light-responsive azobenzene hydrophobic moieties. We present evidence for light triggered membrane permeabilization in the presence azobenzene-modified polymers (AMPs). Exposure to UV or blue light reversibly switches the polarity of the azobenzene (cis−trans isomerization) in AMPs, hence controlling AMP-loaded lipid vesicles permeabilization via in situ activation. Release of encapsulated probes was studied by microscopy on isolated AMP-loaded giant unilamellar vesicles (pol-GUVs). We show that in pH and ionic strength conditions that are biologically relevant pol-GUVs are kept impermeable when they contain predominantly cis-AMPs but become leaky with no membrane breakage upon exposure to blue light due to AMPs switch to a trans-apolar state. In addition, we show that AMPs induce destabilization of plasma membranes when added to mammal cells in their trans-apolar state, with no loss of cell viability. These features make AMPs promising tools for remote control of cell membrane permeabilization in mild conditions.