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Annealing Supramolecular Gels by a Reaction Relay.

ABSTRACT: Supramolecular gels have potential in many areas. In many cases, a major drawback is that the gels are formed at a high rate. As a result, nonoptimal, kinetically trapped self-assembled structures are often formed, leading to gels that can be hard to reproduce and control. One method to get around kinetic trapping is annealing. Thermal annealing is one possibility, but it is not always desirable to heat the gels. Here, we describe a method to anneal pH-triggered gels after they are formed. We employ a reaction relay in a peptide-based hydrogel system to anneal the structures by a controlled and uniform pH change. Our method allows us to prepare gels with more controlled properties. We show that this can be used to enable homogeneous "molding and casting" of the hydrogels. This method of annealing is more effective in improving gel robustness than a conventional heat-cool cycle.

SUBMITTER: Panja S

PROVIDER: S-EPMC7315816 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Annealing Supramolecular Gels by a Reaction Relay.

Panja Santanu S Fuentes-Caparrós Ana M AM Cross Emily R ER Cavalcanti Leide L Adams Dave J DJ

Chemistry of materials : a publication of the American Chemical Society 20200522 12

Supramolecular gels have potential in many areas. In many cases, a major drawback is that the gels are formed at a high rate. As a result, nonoptimal, kinetically trapped self-assembled structures are often formed, leading to gels that can be hard to reproduce and control. One method to get around kinetic trapping is annealing. Thermal annealing is one possibility, but it is not always desirable to heat the gels. Here, we describe a method to anneal pH-triggered gels after they are formed. We em ...[more]

PMID: 32595268

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