Colloidosomes formed by nonpolar/polar/nonpolar nanoball amphiphiles

Co-assembly of Patchy Polymeric Micelles and Protein Molecules

The development in the synthesis and self-assembly of patchy nanoparticles has resulted in the creation of complex hierarchical structures. Co-assembly of polymeric nanoparticles and protein molecules combines the advantages of polymeric materials and biomolecules, and will produce new functional materials. Co-assembly of positively charged patchy micelles and negatively charged bovine serum albumin (BSA) molecules is investigated. The patchy micelles, which were synthesized using block copolymer brushes as templates, leads to co-assembly with protein molecules into vesicular structures. The average size of the assembled structures can be controlled by the molar ratio of BSA to patchy micelles. The assembled structures are dissociated in the presence of trypsin. The protein-polymer hybrid vesicles could find potential applications in medicine.

Solid-supported polymer bilayers formed by coil-coil block copolymers

The formation and physical properties of solid-supported polymer bilayers (SPBs) on an adhesive substrate have been explored by dissipative particle dynamics simulations. A SPB is developed by the adsorption of vesicles formed by diblock copolymers in a selective solvent. The adsorbed vesicle can remain intact or become ruptured into a SPB, depending on the interaction between solvophobic blocks and solvent and the interaction between solvophilic blocks and the substrate. The morphological phase diagram of adsorbed vesicles is acquired. The influence of polymer adhesion strength and solvophobicity on the geometrical and mechanical properties of a SPB is systematically studied as well. It is found that vesicular disruption is easily triggered for strong adhesion strength. Moreover, for strong adhesion strength and weak solvophobicity, the fluctuation of membrane height is impeded while the area of fluctuation is enhanced.

Assembly of Lock-and-Key Colloids Mediated by Polymeric Depletant

Polymer-mediated lock-and-key assembly via depletion attraction is purely a shape-recognition process without any molecular bonding. Since the depletion attraction relates to osmotic pressure and excluded volume, the binding tendency in a dispersion of lock-and-key colloids can be controlled by adjusting the characteristics of polymeric depletants. In this work, dissipative particle dynamics accounting for explicit solvents, polymers, and multiple lock-key pairs are performed to investigate the influences of the polymer concentration, chain length, solvent quality, and chain stiffness. As the polymer concentration associated with osmotic pressure is increased, the binding free energy (E(b)) between a lock-key pair rises linearly and the binding fraction (θ(LK)) in the dispersion grows sigmoidally. Moreover, the increases in the chain length, solvent quality, and chain stiffness lead to the expansion of the polymer size associated with excluded volume and thus both E(b) and θ(LK) rise accordingly. However, E(b) and θ(LK) grow to be insensitive to the chain length for long enough polymer coils but still can be enhanced if the polymer becomes rod-like. As the solvent quality is varied, θ(LK) can be dramatically altered, although the radius of gyration of polymers is slightly changed.