Facile Directed Assembly of Hollow Polymer Nanocapsules within Spontaneously Formed Catanionic Surfactant Vesicles

Abstract

Surfactant vesicles containing monomers in the interior of the bilayer were used to template hollow polymer nanocapsules. This study investigated the formation of surfactant/monomer assemblies by two loading methods, concurrent loading and diffusion loading. The assembly process and the resulting aggregates were investigated with dynamic light scattering, small angle neutron scattering, and small-angle X-ray scattering. Acrylic monomers formed vesicles with a mixture of cationic and anionic surfactants in a broad range of surfactant ratios. Regions with predominant formation of vesicles were broader for compositions containing acrylic monomers compared with blank surfactants. This observation supports the stabilization of the vesicular structure by acrylic monomers. Diffusion loading produced monomer-loaded vesicles unless vesicles were composed from surfactants at the ratios close to the boundary of a vesicular phase region on a phase diagram. Both concurrent-loaded and diffusion-loaded surfactant/monomer vesicles produced hollow polymer nanocapsules upon the polymerization of monomers in the bilayer followed by removal of surfactant scaffolds.

Directed Assembly of Vesicle-Templated Polymer Nanocapsules under Near-Physiological Conditions

“…These data are consistent with our previous report showing a loaded vesicle phase in the greater concentration/surfactant ratio ranges for acrylic monomers compared to styrene monomers. 26 These observations show a slightly different behavior of catanionic surfactant and lipid vesicles loaded with styrene derivatives. Our previous studies of liposomes loaded with styrene monomers showed no noticeable aggregation, suggesting the formation of stable monomer-loaded liposomes.…”

“…24,25 Recently, we reported that bilayers could be loaded with monomers during the vesicle-formation stage (concurrent loading). 2,26 In fact, in certain cases, the presence of monomers favored the spontaneous assembly of surfactants into vesicles. 27 Nanostructures produced by the directed assembly approach show significant promise in different applications.…”

Size‐Selective Yolk‐Shell Nanoreactors with Nanometer‐Thin Porous Polymer Shells

“…As shown previously, the size of intrinsic pores in the wall of vesicle‐templated nanocapsules is less than 0.8 nm 9a–c. To probe the size‐selective permeation through the walls of nanocapsule, we compared the conversion of benzaldehyde and its sterically crowded analogue, 3,5‐di‐ tert ‐butyl benzaldehyde (DTBBA), on Au NRs and on Au@TiO 2 .…”

Hollow polyphosphazene microspheres with cross-linked chemical structure: synthesis, formation mechanism and applications

“…[1][2][3][4] Among the variety of targeted materials, hollow polymer spheres (HPSs) on nanometer and micrometer scales have attracted considerable interest owing to their potential applications as drug carriers, conned reaction vessels, protective shells for cells or enzymes, transfection vectors in gene therapy, carrier systems in heterogeneous catalysis, dye dispersants or as materials for removal of contaminated waste. [8][9][10][11][12][13][14][15] Two of them are particularly interesting and are most commonly used to construct HPSs with controllable structure: self-assembly and sacricial hard template method. [8][9][10][11][12][13][14][15] Two of them are particularly interesting and are most commonly used to construct HPSs with controllable structure: self-assembly and sacricial hard template method.…”

“…[5][6][7] As shown in recent studies, a variety of chemical and physicochemical methods, including emulsion/ interfacial/precipitation polymerization strategies, spraydrying methods, phase inversion technique, self-assembly techniques, so template techniques, and hard template techniques, have been employed to prepare HPSs. In the self-assembly protocol, 6,8,16 the block copolymers are oen used as precursors to prepare hollow spheres and a sequence of steps have to be followed: synthesis of a block copolymer composed of a cross-linkable block and a degradable block, micellization, cross-linking the shell block, and nally, removing the core block by degradation chemically or biologically. In the self-assembly protocol, 6,8,16 the block copolymers are oen used as precursors to prepare hollow spheres and a sequence of steps have to be followed: synthesis of a block copolymer composed of a cross-linkable block and a degradable block, micellization, cross-linking the shell block, and nally, removing the core block by degradation chemically or biologically.…”