Supramolecular Hydrogel Inspired from DNA Structures Mimics Peroxidase Activity.

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Biomimetic Chemistry

Background:

• G-quartet structures are nucleic acid secondary structures with diverse biological roles.
• Supramolecular hydrogels offer versatile platforms for developing functional materials.
• Enzyme-mimicking catalysts are crucial for various chemical and biomedical applications.

Purpose of the Study:

• To synthesize novel supramolecular hydrogels from guanosine and boronic acids.
• To investigate the G-quartet-like self-assembly and properties of these hydrogels.
• To explore the potential of these hydrogels in biomimetic catalysis and sensing.

Main Methods:

• Hydrogel formation using guanosine, boronic acids, and stabilizing cations (K+, Pb2+).
• Characterization of hydrogel self-assembly and structure.
• Assay of peroxidase-like activity using iron(III)-hemin and 3,3',5,5'-tetramethylbenzidine (TMB).
• Development of a molecular logic gate for lead ion sensing based on conformational changes.

Main Results:

• Successful preparation of supramolecular hydrogels from guanosine and boronic acids.
• Demonstration of G-quartet-like self-assembly driven by guanosine boronate esters.
• Observation of peroxidase-like activity in K+-stabilized hydrogels, catalyzing TMB oxidation.
• Conformational switching of G-quartet assemblies induced by K+ and Pb2+ ions.
• Successful implementation of a molecular logic gate for sensing toxic Pb2+ ions.

Conclusions:

• Guano-sine-based supramolecular hydrogels can be formed and exhibit G-quartet-like assemblies.
• These hydrogels possess biomimetic peroxidase activity when complexed with iron(III)-hemin.
• The cation-dependent conformational changes allow for the development of ion-responsive molecular logic gates.
• This work presents a novel approach for creating functional hydrogels for catalysis and sensing applications.