Layer-by-Layer Deposition of Vesicles Mediated by Supramolecular Interactions

Abstract

Vesicles are dynamic supramolecular structures with a bilayer membrane consisting of lipids or synthetic amphiphiles enclosing an aqueous compartment. Lipid vesicles have often been considered as mimics for biological cells. In this paper, we present a novel strategy for the preparation of three-dimensional multilayered structures in which vesicles containing amphiphilic β-cyclodextrin are interconnected by proteins using cyclodextrin guests as bifunctional linker molecules. We compared two pairs of adhesion molecules for the immobilization of vesicles: mannose-concanavalin A and biotin-streptavidin. Microcontact printing and thiol-ene click chemistry were used to prepare suitable substrates for the vesicles. Successful immobilization of intact vesicles through the mannose-concanavalin A and biotin-streptavidin motifs was verified by fluorescence microscopy imaging and dynamic light scattering, while the vesicle adlayer was characterized by quartz crystal microbalance with dissipation monitoring. In the case of the biotin-streptavidin motif, up to six layers of intact vesicles could be immobilized in a layer-by-layer fashion using supramolecular interactions. The construction of vesicle multilayers guided by noncovalent vesicle-vesicle junctions can be taken as a minimal model for artificial biological tissue.

Controlling Multivalent Binding through Surface Chemistry: Model Study on Streptavidin

“…Composite films, in which SAv functions as a supramolecular glue to assemble multiple layers of nano-objects, have also been realized. 19,21 The efficiency of surface functionalization and the stability of the whole surface-confined architecture depend in these systems on the residual valency, i.e., the amount of biotin-binding sites that remain accessible after SAv attachment to the surface.…”

Pentafluorobenzene end-group as a versatile handle for para fluoro “click” functionalization of polythiophenes

“…As a proof of concept for the tethering of biomolecules to P3OT using the PFB molecular handle, we synthesized a previously reported biotinylated thiol derivative 41 and reacted it with P3OT–PFB under the same conditions as other typical thiol nucleophiles. Despite the low solubility of biotin–SH in organic solvents, the reaction proceeded to completion within 12 hours, albeit with a substantial detrimental effect on the solubility of the resulting polymer.…”

“…For example biotin, a molecule extensively studied and used for its strong binding to the protein avidin, was tethered to the mono-functionalized polymer via a thiol linker, opening the door for further biomarkers to be investigated. 41–43 …”

Colloidal interactions induced by overlap of mixed protein+polysaccharide interfacial layers

“…The potentials of the method for the fabrication of films with relatively complex but yet well controlled structures, have been explored in many varied fields of technology, since its introduction (Agarwal, et al, 2010;Aldea-Nunzi, Chan, Man, & Nunzi, 2013;Carosio, Alongi, & Malucelli, 2013;Du, Yang, Zhang, & Jiao, 2009;Johnston, Cortez, Angelatos, & Caruso, 2006;Kochan, Wintgens, Wong, & Melin, 2010;Podsiadlo, et al, 2009;Ramsden, Lvov, & Decher, 1995;Song, et al, 2013). The technique has been extended to include deposition of alternating layers of polymers and small nanoparticles (B. S. Kim, Park, & Hammond, 2008) and, more recently, vesicles (Roling, et al, 2013).…”