A Supramolecular Janus Hyperbranched Polymer and Its Photoresponsive Self-Assembly of Vesicles with Narrow Size Distribution

Abstract

Herein, we report a novel Janus particle and supramolecular block copolymer consisting of two chemically distinct hyperbranched polymers, which is coined as Janus hyperbranched polymer. It is constructed by the noncovalent coupling between a hydrophobic hyperbranched poly(3-ethyl-3-oxetanemethanol) with an apex of an azobenzene (AZO) group and a hydrophilic hyperbranched polyglycerol with an apex of a β-cyclodextrin (CD) group through the specific AZO/CD host-guest interactions. Such an amphiphilic supramolecular polymer resembles a tree together with its root very well in the architecture and can further self-assemble into unilamellar bilayer vesicles with narrow size distribution, which disassembles reversibly under the irradiation of UV light due to the trans-to-cis isomerization of the AZO groups. In addition, the obtained vesicles could further aggregate into colloidal crystal-like close-packed arrays under freeze-drying conditions. The dynamics and mechanism for the self-assembly of vesicles as well as the bilayer structure have been disclosed by a dissipative particle dynamics simulation.

Towards larger spatiotemporal scales in polymer simulations

“…Alternatively in DPD simulations, the effective interaction parameters between CG beads can also be determined by correctly reproducing thermodynamic properties of real systems [13,23]. Recently, Wang et al [24] studied the binding structures of charged dendrimers on model biomembranes.…”

“…These mesoscopic simulation results can provide valuable insight and guidelines for the future synthesis and applications of charged dendrimers as nano-vehicles in gene and drug delivery processes. Similar coarse-graining schemes were also adopted in the studies of the self-assembly of other polymeric materials in dilute solutions and in melts [13,26,27].…”

“…In fields such as polymer and molecular biology, many interesting phenomena occur in length and time scales much bigger than those pertaining to the motion of single atom or molecule. Hence both coarse-grained MD and dissipative particle dynamics (DPD) techniques [3,4] were extensively developed and used in order to allow simulations of complex soft matter systems in larger scales more relevant to these processes [5][6][7][8][9], by omitting degrees of freedom not immediately essential for the description of systems at studied level [10][11][12][13]. For slowly-evolving polymer systems, it is also of great interest to resort to enhanced sampling techniques developed recently for approaching better thermodynamic average calculations [14][15][16][17].…”

Nanoassemblies driven by cyclodextrin-based inclusion complexation

“…32 Zhou and coworkers reported a kind of photoresponsive vesicles constructed by the noncovalent coupling between a hydrophobic hyperbranched poly (3-ethyl-3-oxetanemethanol) with an apex of an AZO group (AZO-HBPO) and a hydrophilic hyperbranched polyglycerol with an apex of a b-CD (CD-HPG). 33 Under the visible light irradiation, an amphiphilic supramolecular dendrimer (HBPO-b-HPG) was formed through the AZO/CD host-guest interaction and such amphiphilic supramolecules can further self-assemble into unilamellar bilayer vesicles with a narrow size distribution. Under the irradiation of UV light, the photoisomerization of AZO from the trans to cis forms induced dissociation of the inclusion complex, which induced the scission of the supramolecular HBPO-b-HPG.…”

Self-Assembly of Hyperbranched Polymers

“…Very recently, they also prepared supramolecular Janus hyperbranched polymer by the noncovalent coupling between the hydrophobic HBPO with an apex of an azobenzene (AZO) group and hydrophilic CD-g-HPG with a CD apex through the specific AZO/CD host À guest interactions (Fig. 2b) [14].…”