Macroscopic Supramolecular Assembly Strategy to Construct 3D Biocompatible Microenvironments with Site-Selective Cell Adhesion

Abstract

Three-dimensional (3D) scaffolds with chemical diversity are significant to direct cell adhesion onto targeted surfaces, which provides solutions to further control over cell fates and even tissue formation. However, the site-specific modification of specific biomolecules to realize selective cell adhesion has been a challenge with the current methods when building 3D scaffolds. Conventional methods of immersing as-prepared structures in solutions of biomolecules lead to nonselective adsorption; recent printing methods have to address the problem of switching multiple nozzles containing different biomolecules. The recently developed concept of macroscopic supramolecular assembly (MSA) based on the idea of "modular assembly" is promising to fabricate such 3D scaffolds with advantages of flexible design and combination of diverse modules with different surface chemistry. Herein we report an MSA method to fabricate 3D ordered structures with internal chemical diversity for site-selective cell adhesion. The 3D structure is prepared via 3D alignment of polydimethylsiloxane (PDMS) building blocks with magnetic pick-and-place operation and subsequent interfacial bindings between PDMS based on host/guest molecular recognition. The site-specific cell affinity is realized by distributing targeted building blocks that are modified with polylysine molecules of opposite chiralities: PDMS modified with films containing poly-L-lysine (PLL) show higher cell density than those with poly-D-lysine (PDL). This principle of selective cell adhesion directed simply by spatial distribution of chiral molecules has been proven effective for five different cell lines. This facile MSA strategy holds promise to build complex 3D microenvironment with on-demand chemical/biological diversities, which is meaningful to study cell/material interactions and even tissue formation.

Three-Dimensional Printable Enzymatically Active Plastics

“…This maintenance of activity is a distinct advantage, as this increases the functional lifetime of the material in comparison to materials that only have a monolayer of an active component. This particularly promising for the fabrication of medically relevant bioactive implants and tools, where surface-functionalized materials have shown immense success for tissue culture and growth promotion, − and the preservation of activity would greatly increase the viable lifetime of implants and implements.…”

Robust Electrostatically Interactive Hydrogel Coatings for Macroscopic Supramolecular Assembly via Rapid Wet Adhesion

“…Compared with the current limited option of polyelectrolyte multilayers as a flexible spacing coating, the PHEMA hydrogel coating is superior in broadening the simplification of fabrication on both steps and constituents and improving the robustness to environment changes. We envision that the PHEMA flexible spacing coating could broaden the applicable material choices of the macroscopic self-assembly and provide novel solutions to wet adhesion, an integration of heterogeneous materials, ,, programmable materials, , and so on.…”

“…Owing to the characteristics of interfacial interactions between micrometer-to-millimeter surfaces, studies of the MSA mechanism are used to understand diverse non-covalent interfacial phenomena such as bio-/wet adhesion, 12,13 self-healing. 14−16 Meanwhile, MSA has been developed as a facile modular fabrication strategy to prepare heterogeneous structures, 17 bio-scaffolds, 18,19 actuators, 20 and information storage materials. 21−23 To extend the applicable scenarios of MSA, much progress has been achieved on enriching supramolecular interactions (molecular recognition, 1,24 hydrogen bonding, 8 electrostatic interactions, 25 DNA hybridization, 4,9 and so on), extending building block materials (gels, 1,4,[8][9][10]26 elastomers, 25,27,28 quartz, and metal 17 ) that could realize MSA, and revealing the assembly mechanism.…”

“…Compared with previous polyelectrolyte multilayers, the flexible spacing coating of the PHEMA hydrogel is advantageous in a facile fabrication, simplified constituents, stability in solvents, and photoreactivity for potential uses of surface patterning. We envision that the PHEMA hydrogel coating could broaden the applicable materials of flexible spacing coatings, which is meaningful for both an efficient MSA and interfacial adhesion widely concerned in advanced uses in wet adhesion, 13 soft electronics, 37 encoding, 23 scaffolds, 19 and metamaterials. 38…”

Macroscopic Supramolecular Assembly of Rigid Building Blocks Facilitated by Layer-By-Layer Assembled Microgel Film

“…Macroscopic supramolecular assembly (MSA) focuses on the study of multivalent events of numerous non-covalently interactive moieties modified on building blocks larger than a micrometer. − Taking advantage of abundant supramolecular interactions and delicate design of building blocks, MSA has been newly progressed in supramolecular science for their potential applications in biomaterials, − information encoding and storage, , and fabrication of ordered structures , and as an ideal platform to investigate the mechanism of underwater adhesion, , self-healing, and so forth. Although originating from molecular assembly, the mechanism of MSA is complex and difficult because MSA requires multivalent interactions of numerous supramolecular groups anchored on the macroscopic surfaces to effectively associate large building blocks.…”