Advancing protein-based biomaterials

Biomaterials research has rapidly advanced in recent years, with the development of novel materials that can be used in various fields such as biomedicine, agriculture, and others. Protein-based biomaterials have especially gained attention due to their biocompatibility and biodegradability. This project contributes to the field of biomaterials by demonstrating the potential of using whey protein isolate which were functionalised through methacrylation and cross-linked using UV-initiated photo-polymerisation to create photo-responsive hydrogels. By comparing various protein structural forms [globular and fibrils] and different manufacturing techniques, the study also provides insights into how these factors affect the properties of the resulting hydrogels. Finally, a horticultural case study highlights the versatility of the developed protein-based biomaterials and their potential impact on sustainable horticultural practices. Results from this study reveal that the protein-based biomaterials produced using whey protein isolate are compatible with various processing methods, such as moulding and 3D printing. Changing the quaternary structure of the protein significantly alters the properties of the resulting hydrogels, with globular protein formulations showing higher yield stress values (ranging between 1970 ± 327.4 Pa and 1446.8 ± 287.7 Pa) compared to fibril formulations (ranging between 588.1 ± 59.4 Pa and 352.3 ± 102.0 Pa). Due to the lyophilisation process which led to the fragmentation of the original long fibrils into shorter rod-shaped structures, the fibril length proved inadequate to contribute to gel strength. The incorporation of ceramic particles into selected formulations did not improve the mechanical properties of the hydrogels. Swelling investigations demonstrated the anionic property of the materials, with higher swelling percentages (< 100%) in neutral (pH7) and alkaline (pH11) conditions and lower values (> 2%) in acidic condition (pH2). Additionally, a horticultural case-study using dwarf beans was conducted to assess the real-world performance of the hydrogels in the soil. This in-house method involved growing plants in soil with and without hydrogels, and results showed a survival rate of 83.3% and root lengths averaging 217.1 ± 47.6 mm compared to 187.8 ± 10.3 mm in the control group. The goal of this research is to create multifunctional and biocompatible biomaterials applicable in multiple domains. Thus, this study illustrates the potential of various protein functionalisation techniques in crafting innovative and sustainable biomaterials. The successful formulation of methacrylated whey protein isolate marks a significant step forward in the field of protein-based biomaterials, offering a promising platform for further research.

Name thesis:degree_name

PhD

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Chemical Sciences

Grantor dc:publisher

ResearchSpace@Auckland

Year dc:date.issued

2023

Author dc:creator

• Agnieray, Heiana

Advisors dc:contributor.advisor

• Gerrard, Juliet
• Domigan, Laura

• whey protein isolate
• photopolymerisation
• 3D printing
• hydrogel

Statement dc:rights

• Items in ResearchSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Licence dc:rights.uri

• https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm

Handle dc:identifier.uri

https://hdl.handle.net/2292/72191

OAI identifier oai:identifier

oai:researchspace.auckland.ac.nz:2292/72191