Surface‐Assisted Self‐Assembly Strategies Leading to Supramolecular Hydrogels

Abstract

Localized molecular self-assembly processes leading to the growth of nanostructures exclusively from the surface of a material is one of the great challenges in surface chemistry. In the last decade, several works have been reported on the ability of modified or unmodified surfaces to manage the self-assembly of low-molecular-weight hydrogelators (LMWH) resulting in localized supramolecular hydrogel coatings mainly based on nanofiber architectures. This Minireview highlights all strategies that have emerged recently to initiate and localize LMWH supramolecular hydrogel formation, their related fundamental issues and applications.

Supported Catalytically Active Supramolecular Hydrogels for Continuous Flow Chemistry

“…In the case of peptide‐based hydrogels, a first technological issue that needs to be resolved is the spatial localization of the hydrogel growth from the surface of the polymer foam in order to link the hydrogel and the polymer material. This can be achieved by immobilizing a (bio)catalyst on a planar surface . We immobilized an enzyme that is able to transform non‐self‐assembling precursors present in solution into self‐assembling building blocks on the surface .…”

Photocontrolled Hierarchical Self‐Assembly of Anisotropic Micropatterns of Nanofibers onto Isotropic Surfaces

“…Evolution in the research on low molecular weight gelators (LMWGs) as building blocks for bottom‐up approaches in nanotechnology has resulted in very promising alternatives to better‐known chemical polymers. Indeed, directed self‐assembly on liquid–oil interfaces by enzyme activation, from the surface of modified nanoparticles by controlling the pH or by using modified surfaces was demonstrated. LMWGs, small molecules that bind reversibly by weak interactions forming physical gels, differ from covalently binding polymeric gel‐precursors and can be designed to be stimuli‐responsive and widely applicable.…”

“…[20] In the case of a diazobenzenederivative alignment layer, it is required to first entirely cover the whole surface at high temperature (e.g., 110 °C) with a substrate that is, and remains, photosensitive even after the first irradiation (multiple irradiations are used to pattern): [21] this opens up potential limitations regarding optical transparency and photostability in the visible light range of the substrate, and the impossibility to create noncoated gaps on the surface or changing the chemical nature of the aligning substrate.Evolution in the research on low molecular weight gelators (LMWGs) as building blocks for bottom-up approaches in nanotechnology has resulted in very promising alternatives to better-known chemical polymers. Indeed, directed selfassembly on liquid-oil interfaces by enzyme activation, [22] from the surface of modified nanoparticles by controlling the pH [23] or by using modified surfaces [24] was demonstrated. LMWGs, small molecules that bind reversibly by weak interactions forming physical gels, differ from covalently binding polymeric gel-precursors and can be designed to be stimuli-responsive and widely applicable.…”

Nanostructured Biointerfaces Based on Bioceramic Calcium Carbonate/Hydrogel Coatings on Titanium with an Active Enzyme for Stimulating Osteoblasts Growth

“…Furthermore, it has been immobilized onto the alginate, silk, and gellan gum‐based as 3D scaffold materials for bone tissue healing applications. It was reported in many of these studies that functionalization of Ti implant or hydrogel scaffold surfaces with ALP has considerably facilitated bone tissue integration or healing.…”