Polymerization in Polymerizable Vesicle Bilayer Membranes

Abstract

Polymerization reactions in lyotropic liquid crystalline phases have opened the way to the development of many novel materials. Inter alia, the two-dimensional self-assembly of amphiphiles in vesicle bilayers has attracted considerable interest as an ordered reaction medium. In this study we follow three different routes to polymerize within vesicle bilayer membranes with a view to preparing novel vesicle−polymer colloids. First, we study the vesicle formation and the polymerization of functional amphiphiles carrying one or two styryl groups. A combination of characterization techniques gives insights into bilayer properties, polymerization kinetics, and vesicle morphology of these (polymerized) vesicles. On the basis of this reference system, we explore the copolymerization of monomers inserted in the matrix of polymerizable amphiphiles. On the basis of kinetic and morphological data we prove that the copolymerization is viable if the polymerizable moieties are adequately chosen with respect to reactivity and location within the amphiphile matrix. Extremely deformed, albeit stable, vesicles are induced by cross-linking inserted monomers with monofunctional amphiphiles. In a last step, we attempt the synthesis of two-dimensional interpenetrating networks employing the previously polymerized amphiphile networks as templates. The cross-linking of divinylbenzene within cross-linked membranes affords peculiar orange-skin-like bilayer morphologies and gives evidence of the feasibility of the concept. Throughout the study, cryogenic electron microscopy appears as an indispensable means to unravel the morphology of the obtained vesicle−polymer architectures.

Synthetic Bilayer Fragments for Solubilization of Amphotericin B

“…The extreme versatility of supramolecular assemblies (1,2), among them the bilayers (3), can be advantageously explored for the controlled construction of new materials (4)(5)(6)(7)(8)(9)(10)(11). From the observation of biological wisdom in nature, it has been recognized that intermolecular interactions form the basis of highly specific recognition, reaction, transport and regulation processes as enzymatic reactions, substrate binding, transcription and translation of genes, and cellular recognition.…”

“…From the observation of biological wisdom in nature, it has been recognized that intermolecular interactions form the basis of highly specific recognition, reaction, transport and regulation processes as enzymatic reactions, substrate binding, transcription and translation of genes, and cellular recognition. Vesicles and other bilayer assemblies, though ephemerous, produce useful devices by either depositing onto polymeric, mineral, or biological surfaces (3)(4)(5)(6)(7) or acting as templates for direction of inorganic matter deposition, redox processes, or polymerization reactions (8)(9)(10)(11). In biology and medicine, they offer a suitable matrix to solubilize and/or carry drugs (12)(13)(14)(15)(16)(17)(18)(19) or biomolecules (20)(21)(22)(23)(24), either as entire entities or as complexes with the biomolecule or drug to be carried.…”

Surface-Modified Porous Polymeric Membrane Using Vesicles

“…A surfactant of ammonium salt whose chemical structure is very similar to that of BDAC was also reported not to form vesicles. 8 Probably, the bulky phenyl group at each hydrophobic chain terminus may prevent the molecule from assembling in a bilayer. On the other hand, even before ultrasonication, the hydrated BPAS did form vesicles whose size distribution was bimoidal with mean diameters of about 60 nm and 250 nm, respectively, as shown in Figure 4.…”

Vesicle Templating

“…Enforced bilayer vesicles are promising for the circumvention or minimization of such deformations. To this end we have synthesized enforced vesicles [11] upon co-polymerization of mono-functional surfactant with cross-linker (Fig. 4).…”