Thermoresponsive BSA hydrogels with phase tunability

Area of Science:

• Biomaterials Science
• Protein Engineering
• Nanotechnology

Background:

• Amyloids, protein aggregates with β-sheet structures, are linked to neurodegenerative diseases but also offer potential for bionanotechnology.
• Amyloid fibrillar networks can form stable hydrogels under specific conditions, presenting opportunities for novel biomaterials.

Purpose of the Study:

• To investigate the formation and properties of thermally-induced hydrogels using bovine serum albumin (BSA) as a model amyloidogenic protein.
• To explore the tunability of sol-gel-sol transitions and assess the suitability of these hydrogels for drug delivery applications.

Main Methods:

• Utilized high concentrations of BSA (14-22% w/v) heated at 65°C for short durations (<3 min) to induce gelation without cross-linkers.
• Characterized gel properties using visual inspection, rheology, electron microscopy, fluorescence spectroscopy, UV-visible spectroscopy, and circular dichroism spectroscopy.
• Assessed drug release kinetics and cytocompatibility of the reversed sol with HaCaT skin cell lines.

Main Results:

• Achieved rapid, injectable, non-toxic BSA hydrogels with tunable sol-gel-sol transitions over minutes to days.
• Identified optimal gelation temperatures between 60-70°C and demonstrated that increased protein concentration reduced gelation time.
• Observed zero-order drug release kinetics and confirmed cytocompatibility of the reversed sol, indicating suitability for topical applications.

Conclusions:

• Developed a rapid, crosslinker-free, thermoresponsive BSA hydrogelation method with controllable properties.
• The tunable nature and cytocompatibility of these BSA hydrogels make them promising for topical drug delivery systems.