Stable and Fluid Multilayer Phospholipid–Silica Thin Films: Mimicking Active Multi-lamellar Biological Assemblies

Abstract

Phospholipid-based nanomaterials are of interest in several applications including drug delivery, sensing, energy harvesting, and as model systems in basic research. However, a general challenge in creating functional hybrid biomaterials from phospholipid assemblies is their fragility, instability in air, insolubility in water, and the difficulty of integrating them into useful composites that retain or enhance the properties of interest, therefore limiting there use in integrated devices. We document the synthesis and characterization of highly ordered and stable phospholipid-silica thin films that resemble multilamellar architectures present in nature such as the myelin sheath. We have used a near room temperature chemical vapor deposition method to synthesize these robust functional materials. Highly ordered lipid films are exposed to vapors of silica precursor resulting in the formation of nanostructured hybrid assemblies. This process is simple, scalable, and offers advantages such as exclusion of ethanol and no (or minimal) need for exposure to mineral acids, which are generally required in conventional sol-gel synthesis strategies. The structure of the phospholipid-silica assemblies can be tuned to either lamellar or hexagonal organization depending on the synthesis conditions. The phospholipid-silica films exhibit long-term structural stability in air as well as when placed in aqueous solutions and maintain their fluidity under aqueous or humid conditions. This platform provides a model for robust implementation of phospholipid multilayers and a means toward future applications of functional phospholipid supramolecular assemblies in device integration.

Dual-tuning multidimensional superstructures based on a T-shaped molecule: vesicle, helix, membrane and nanofiber-constructed gel

“…Therefore, the self-assembly process promotes the transform of sol-gel and improves the thermal stability. 35 Compared with the helical bers at 0.2 wt% FG, the gels (0.5, 1 wt% FG), a 3D network of gel bers lled with solvent, are closed to the solid crystal, which is consistent with the properties of rheological measurements. These gels possess strong strength and well-ordered orientation of molecules.…”

Nanostructured Lipid‐Based Films for Substrate‐Mediated Applications in Biotechnology

“…Based on the direct spreading method, Gupta et al [92] introduced a way to construct lipid-based multilamellar films with improved structural integrity. The authors have prepared composite lipid-silica films by spin-coating the lipids onto a substrate first and then exposing lipid film to vapors of a silica precursor, tetraethyl orthosilicate (TEOS), as schematically shown in Fig.…”

“…When lipids films are exposed to a silica precursor/water vapor environment, silica locate between lipid bilayers (represented in green). Adapted from [92] . Copyright 2013 American Chemical Society.…”

Multi-Stacked Supported Lipid Bilayer Micropatterning through Polymer Stencil Lift-Off

“…A number of strategies have been developed for building stacked SLBs from the bottom-up in vitro . Electrostatic interactions between cationic and anionic lipid bilayers [ 9 ] and between phospholipids and silica templates [ 10 ] have been used to form double stacked bilayers and highly ordered hybrid multilamellar assemblies respectively. In addition, specific biological interactions involving biotin-streptavidin coupling [ 11 ] and DNA hybridization [ 12 ], as well as covalent bonds involving inter-bilayer maleimide-thiol coupling [ 13 ], have been used to form double bilayer systems with variable stability.…”