Biocytin-Based pH-Stimuli Responsive Supramolecular Multivariant Hydrogelator for Potential Applications

Area of Science:

• Biomaterials Science
• Supramolecular Chemistry
• Biomedical Engineering

Background:

• Self-assembly is a key method for creating biomaterials, particularly hydrogels, from small molecules.
• d-biotin (vitamin B) and biocytin are biologically significant molecules with limited hydrogel applications.
• Biocytin is an amidation product of d-biotin and l-lysine.

Purpose of the Study:

• To develop a novel pH-stimuli responsive supramolecular hydrogel based on biocytin.
• To explore the potential of d-biotin, biocytin, and l-lysine in biomedical fields through hydrogel formation.
• To create a new class of biomaterials using biocytin for advanced applications.

Main Methods:

• Synthesis of N_α-(fluorenylmethoxycarbonyl)-d-biocytin) [FmB] hydrogelator.
• Characterization of pH-dependent hydrogelation, thixotropy, and thermal reversibility.
• Electron microscopy, CD, FT-IR, fluorescence, and powder XRD for structural analysis.
• In vitro cell viability and bactericidal activity assays against Escherichia coli.

Main Results:

• FmB hydrogel exhibited pH-dependent gelation, with thixotropic and thermally reversible properties at physiological pH.
• A supergelator nature was observed at acidic pH.
• Electron microscopy revealed a fibrous network structure stabilized by intermolecular interactions (aromatic, hydrogen bonding).
• The FmB hydrogel demonstrated cell viability and specific bactericidal activity against E. coli.

Conclusions:

• A novel pH-responsive biocytin-based supramolecular hydrogel (FmB) was successfully developed.
• The hydrogel possesses a fibrous network structure with tunable properties based on pH.
• The FmB hydrogel is biocompatible and exhibits antimicrobial properties, suggesting its utility as a self-delivery system.
• This work significantly expands the biomedical applications of biotin and biocytin derivatives.