Supported Catalytically Active Supramolecular Hydrogels for Continuous Flow Chemistry

Abstract

Inspired by biology, one current goal in supramolecular chemistry is to control the emergence of new functionalities arising from the self‐assembly of molecules. In particular, some peptides can self‐assemble and generate exceptionally catalytically active fibrous networks able to underpin hydrogels. Unfortunately, the mechanical fragility of these materials is incompatible with process developments, relaying this exciting field to academic curiosity. Here, we show that this drawback can be circumvented by enzyme‐assisted self‐assembly of peptides initiated at the walls of a supporting porous material. We applied this strategy to grow an esterase‐like catalytically active supramolecular hydrogel (CASH) in an open‐cell polymer foam, filling the whole interior space. Our supported CASH material is highly efficient towards inactivated esters and enables the kinetic resolution of racemates. This hybrid material is robust enough to be used in continuous flow reactors, and is reusable and stable over months.

Peptide Hydrogels Assembled from Enzyme-Adsorbed Mesoporous Silica Nanostructures for Thermoresponsive Doxorubicin Release

“…), this approach is particularly suitable for biomedical applications . In addition, thanks to the enzyme location, the hydrogelation can be spatially controlled, which has been recently illustrated for various applications. − …”

Biopolymer-supramolecular polymer hybrids for photocatalytic hydrogen production

“…10 These types of photocatalytic hydrogel materials can ''heterogenize'' otherwise homogeneous catalysts by entrapping them in a polymeric matrix and are composed of interconnected fluid compartments that allow for rapid diffusion. [14][15][16][17][18] Our group has previously reported on a number of negatively charged chromophore amphiphiles that self-assemble in water through p-p stacking into micron-long supramolecular assemblies with molecular thickness that are capable of intermolecular charge transport for photocatalysis. [5][6][7][8][9][10][11][12][13][19][20][21] Of interest to this study is a perylene monoimide substituted by an ionizable carboxylated tail with five methylene units (PMI-L5) which has been used to photosensitize catalysts for the hydrogen evolution reaction (HER).…”

Chemical Transformations in Supramolecular Hydrogels

“…As a result, the catalytic hydrolysis reactions are timeconsuming, tedious, and sometime expensive utilizing the supramolecular hydrogels. To overcome these problems, Fores et al 36 developed a strategy to grow a catalytically active supramolecular hydrogel in an open-cell melamine foam. An enzyme, alkaline phosphatase, was installed in the porous wall of the foam, which can catalyze in situ formation of the Fmoc-GFFYGHY peptide hydrogelator (OC-9) from the bis- phosphorylated peptide (Table 1, entry 3), resulting the formation of the hydrogel network inside the polymer foam.…”