Advances on vortex fluidics for processing soft matter nanomaterials

Author: Nikita Joseph

Joseph, Nikita, 2021 Advances on vortex fluidics for processing soft matter nanomaterials, Flinders University, College of Science and Engineering

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Abstract

The Vortex Fluidic Device (VFD) is a versatile microfluidic platform with a range of applications under its umbrella. In this thesis, the research is focused on developing applications for the soft-matter discipline in manipulating soft-materials at nano-domains. The VFD imparts controlled mechanical energy and shear stress in the thin-film liquid in the device. Soft-materials can be easily manipulated under this controlled mechano-energy. Crucial parameters such as controlled size, shape and scalability are some challenges which determines the fate of any new technology coming in the market. In this thesis VFD gives a new direction to these challenges via a cost-effective and a sustainable pathway for food, pharmaceuticals and cosmetic industries.

A process for fabricating soft-nanoparticles such as Water/Oil/Water (W/O/W) emulsions is demonstrated in a scalable environment. The mechano-energy of the liquid in the VFD controls the size of these particles at the nanometer dimensions. Parameters such as flow-rate, rotational-speed are altered for a favorable application in the food-industry. A number of different food models have been tested in determining the potential of VFD in the food technology sector. From improving the time-efficiency in raw milk pasteurization to improving enzymatic hydrolysis of the milk powder has been established for providing a sustainable environment for the benefit of the community in day to day life. In addition, improved O/W formulation with higher nutritional values has been established in the VFD. This process provides a new route in the health industry where fish-oil is often under-rated due to its taste, odor, chemical structure and viscosity.

With increasing customer demand for plant-based material and super foods with better nutritional values in terms of protein or vitamins there is always a research niche awaiting. Herein, we utilize the potential of VFD in fabricating stronger gelatin gels when cross-linked with polyphenols non-covalently. These crosslinked gels are further utilized to entrap nutrients without using any toxic chemicals or reagents which unequivocally meets the criteria of green chemistry metrics. These mentioned applications embrace major challenges in the food technology sector and have given a new direction for the VFD technology.

Moreover, with this VFD thin-film microfluidic flow reactor one of the widely utilized soft material in health, food and pharmaceutical industry “liposomes” are fabricated. Liposomes of ca 100 nm are fabricated from a phospholipid suspension when processed at its optimized conditions in the VFD. This study also includes the in-situ small angle neutron scattering which reveals ca 100 nm are the stable bottom-up self-assembly process thermodynamically, and this is in accord with cellular processing of exosomes and endosomes which are of similar dimensions.

Overall, the results in this thesis further contribute to the remarkable versatility of the VFD. It is a new cutting-edge technology in the field of microfluidics with a plethora of applications and provides insights on the rudimentary disciplines of science. It is a benign process intensification platform which is high in green chemistry metrics and the applications exhibited in this thesis opens are just the start to the future applications.

Keywords: Vortex Fluidic Device, Nanomaterials, Soft Matter, Fishoil, liposomes.

Subject: Chemistry thesis

Thesis type: Doctor of Philosophy
Completed: 2021
School: College of Science and Engineering
Supervisor: Prof. Colin Raston