Polymeric Amphiphile Branching Leads to Rare Nanodisc Shaped Planar Self-Assemblies

Abstract

Self-assembly is fundamental to the biological function of cells and the fabrication of nanomaterials. However, the origin of the shape of various self-assemblies, such as the shape of cells, is not altogether clear. Polymeric, oligomeric, or low molecular weight amphiphiles are a rich source of nanomaterials, and controlling their self-assembly is the route to tailored nanosystems with specific functionalities. Here, we provide direct evidence that a particular molecular architecture, polymeric branching, leads to a rare form of self-assembly, the planar nanodisc. Cholesterol containing self-assemblies formed from amphiphilic linear or branched cetyl poly(ethylenimine) (Mn approximately 1000 Da) or amphiphilic cetyl poly(propylenimine) dendrimer derivatives (Mn approximately 2000 Da) show that branching, by reducing the hydrophilic headgroup area, alters the shape of the self-assemblies transforming closed 60 nm spherical bilayer vesicles to rare 50 nm x 10 nm planar bilayer discs. Increasing the hydrophilic headgroup area, by the inclusion of methoxy poly(ethylene glycol) moieties into the amphiphilic headgroup, transforms the planar discs to 100 nm spherical bilayer vesicles. This study provides insight into the key role played by molecular shape on molecular self-organization into rare nanodiscs.

Surface‐Reactive Patchy Nanoparticles and Nanodiscs Prepared by Tandem Nanoprecipitation and Internal Phase Separation

“…The nanodiscs may have particular interfacial properties at liquid–liquid interfaces but also with biological membranes. Such flat anisotropic disc‐like nanostructures are rather rare in the synthetic realm, yet a famous example in the biological context is that of phospholipid/membrane protein co‐assembly . Further research should be dealing with corresponding patterned immobilization of biomolecular modules, as well as expanding the method to other kind of polymers, such as biocompatible or (bio)degradable counterparts.…”

Nano self-assemblies based on cholate grafted poly-L-lysine enhanced the solubility of sterol-like drugs

“…PLL-CA and PLL-PAL, self-assembled in aqueous solution after probe sonication due to the amphiphilicity nature of the polymers, irrespective of the structure of pendant groups. Previous studies have proven that the supramolecular structures formed by amphphilic graft copolymers transform from polymeric micelle to solid nanoparticle with the increase of hydrophobicity (Wang et al, 2004;Qu et al, 2008). Polymeric micelle will be formed by graft copolymers with relatively low level of hydrophobic grafting, e.g.…”

“…The hydrophobic pendant grafting level of PLL-CA and PLL-PAL was evaluated based on the method reported in the previous works (Gu et al, 2008;Qu et al, 2008;Thompson et al, 2008), which was calculated by the comparison of the C/N ratio of the graft polymer to the parent PLL.…”

“…Compared to block copolymers, the investigation on amphiphilic graft copolymers bearing 'drug-like' pendant groups for enhancing the solubilisation of poorly watersoluble drugs is rarely reported, albeit several papers have published the work related to the self-assembly (Wang et al, 2004;Gu et al, 2008;Qu et al, 2008;Thompson et al, 2008) and drug delivery properties of amphiphilic graft copolymers (van Krevelen, 1997;Francis et al, 2003;Cheng et al, 2006). Unlike those block copolymer micelles (Mahmuda et al, 2008(Mahmuda et al, , 2009, it is noteworthy that the pendant group of graft copolymers could be the only hydrophobic moiety that will form the hydrophobic microdomains and contribute to the major interaction with the hydrophobic drug molecules.…”

Preparation and Characterization of Nano-Sized (Mg<sub>(x)</sub>Fe<sub>(1–x)</sub>O/SiO<sub>2</sub>) (x = 0.1) Core-Shell Nanoparticles by Chemical Precipitation Method

“…The Developing new synthesis techniques make it possible to synthesize not only the symmetrical (spherical) shape nanoparticles but also a variety of other shapes such as cube, hexagon [9], prism [10], octahedron [11], disk [12], wire, rod and tube [13] etc.magnetic coreshell NPs are also used in important bio applications, including magnetic bio separation and detection of biological entities (cell, protein, nucleic acids, enzyme, bacterial, virus, etc. ),clinic diagnosis and therapy (such as MRI (magnetic resonance image) and MFH (magnetic fluid hyperthermia), targeted drug delivery and biological labels [14].…”