title: Permeabilization of lipid membranes and cells by a light-responsive copolymer.
abstract: 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.
authors: Laboratoire de Physico-chimie des polymères et des milieux dispersés, ESPCI, UPMC & CNRS UMR 7615, 10 rue Vauquelin, 75005 Paris, France. sarra.sebai@espci.fr
authors: Sarra C
authors: SC
authors: Sebai
authors: Sophie
authors: S
authors: Cribier
authors: Ali
authors: A
authors: Karimi
authors: Dominique
authors: D
authors: Massotte
authors: Christophe
authors: C
authors: Tribet
mesh_terms: D000180:Acrylic Resins / Q000138:chemical synthesis / Q000737:chemistry*; D000818:Animals; D001391:Azo Compounds / Q000737:chemistry; D019556:COS Cells; D002463:Cell Membrane Permeability; D002470:Cell Survival; D002478:Cells, Cultured; D002522:Chlorocebus aethiops; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D008027:Light; D008563:Membrane Lipids / Q000737:chemistry*; D015394:Molecular Structure; D009994:Osmolar Concentration; D013499:Surface Properties
chemical_list: D000180:Acrylic Resins; D001391:Azo Compounds; D008563:Membrane Lipids; C006903:carbopol 940; C009850:azobenzene