Date of Award

Summer 8-18-2023

Level of Access Assigned by Author

Open-Access Thesis

Degree Name

Master of Science (MS)


Biological Engineering


Michael D. Mason

Second Committee Member

Deborah Bouchard

Third Committee Member

Evan Wujcik


Aquaculture has shown significant growth within the past few decades and is expected to continue expanding rapidly as the global demand for fish consumption continues to increase. A significant loss within the aquaculture industry is due to pathogen transmission within the farm systems. These pathogens are mitigated through various methods that are not cost effective or have limited protection. The most common method of pathogen mitigation is through oil-based injection vaccines as they provide even protection across vaccinated fish and provides the longest protection compared to other vaccination methods. These oil-based injection vaccines are not without their flaws as they require multiple injections throughout the lifecycle of the fish which creates unwanted handling and increased costs. Oil-based injection vaccines have also been shown to cause adverse reactions within the fish. From preliminary tests, it was determined that cellulose nanomaterials have minimal adverse reactions when injected and does not significantly affect the growth of the fish.

The goal of this research was to develop an improved adjuvant that can create an immune response comparable to the current mineral oil-based adjuvant, decrease adverse effects, and improve the time of immunity. The ability for the developed adjuvant to have a prolonged release of antigen would remove the need for multiple injections that are currently used for long term immunity. One method for prolonged release of materials is with hydrogels which are currently being used in drug diffusion applications. A cellulose nanomaterial polymer hydrogel matrix offers improved biocompatibility, sustainability, tunability, and affordability. The development of a physically crosslinked hydrogel formulation and the modifications required for ease of delivery was first attempted. Even with modification these physically crosslinked hydrogels were too invasive and time intensive. The development of a chemically modified, shear thinning cellulose nanomaterial polymer was then synthesized, modified for improved injection characteristics, assessed for mechanical properties, assessed for chemical properties, and in vivo tested for the analysis of adverse reactions and ease of administration compared to the physically crosslinked hydrogel.