The Formation and Characterisation of Protein Bigels
Bigels can be described as double network systems that consist of two discrete but interpenetrating gel networks that each contribute to the mechanical properties of the gel producing a much stronger more robust gel. The first protein-protein bigel consisting of BSA and gelatin in a 9:10 ratio, was previously described by my colleagues in 2015 (Blumlein and McManus, 2015). The method of preparation for these bigels was optimised and standardised for consistency amongst future measurements. New proteins were then explored as potential candidates for the bigels. New proteins were carefully chosen based on their physio-chemical properties. Then, by tuning the conditions of the protein solution it is possible to control the kinetics of the gelation procedure, ensuring that both gel systems form independently of one another. A new bigel was formed from ovalbumin and gelatin with an elastic modulus of 67 kPa, much greater than previously recorded. In addition, the gels exhibited a high degree of elasticity, with 85 % reversibility recorded. These mechanical properties were all determined using cavitation rheology. As previously reported with the original BSA/gelatin bigel, these newly formed bigels are much stronger than the combined elastic moduli of their parent gels. Preliminary cellular studies showed a positive growth response towards the bigels when compared with collagen scaffolds and untreated wells, which in combination with their biocompatibility, biodegradability and mechanical strength highlights the huge potential these bigels have for biomedical applications such as drug delivery, wound healing and in particular stress-bearing applications such as replacement bone, ligament and cartilage.
National University of Ireland - Maynooth
Networked Digital Library of Theses and Dissertations