Microfluidic Electrofiltration: An Enabling Technology for Label-Free Isolation of Exosomes
Creators: name: Hassanpour-Tamrin, Sara
Publisher: name: Graduate Studies
Year: 2023
Subjects: subject: Extracellular vesicles
subject: Exosomes
subject: Microfluidics
subject: Microfluidic isolation
subject: Nanoparticles
subject: Exosome isolation
subject: Label-free isolation
subject: Nanoparticle separation
subject: Charged nanoparticles
subject: Isolation of charged nanoparticles
subject: Electrokinetic separation
subject: Electrophoretic separation
subject: Electrically assisted separation
subject: Electrofiltration
subject: Electrically assisted filtration
subject: Isolation technology
subject: Engineering--Biomedical

description: Exosomes are cell-derived nanostructures, ranging in size from 30 nm to 150 nm, found in biological fluids. They carry a bioactive cargo and play significant roles in physiological and pathological processes. While their potential as diagnostic and therapeutic tools have been unveiled, uncertainties regarding their nature continue to hinder their widespread application. A significant problem currently acting as a bottleneck in the rapidly burgeoning field of exosome research is an inability to efficiently and with high yield separate pure exosomes from other unwanted components present in biological fluids. In comparison to conventional methods, microfluidic separation systems have demonstrated great potential for achieving rapid exosome isolation from biological fluids. However, current microfluidic systems often rely on label-based methods using capture molecules, which may have limitations in capturing diverse exosome populations and altering the natural state of exosomes, thus compromising downstream analyses for clinical applications. On the other hand, existing label-free microfluidic platforms are not specifically designed for exosome isolation, potentially leading to the co-purification of small impurities. Therefore, there is a pressing need for the development of novel label-free microfluidic techniques to isolate exosomes from biological fluids in an efficient and effective manner. The studies conducted during this dissertation led to the development of an electrical-based microfluidic platform, named "On-Chip electrofiltration", combining filtration and electrophoresis techniques to separate exosomes from other unwanted particles in the cell culture supernatant. This platform targets the physical properties of exosomes, including size and surface charge, and offers significant advantages in terms of cost, processing time, simplicity, and reproducibility, while preserving the native characteristics of exosomes for clinical applications. The outcome of this project significantly advances our understanding of the electrical properties of exosomes and biological fluids, paving the way for the development of new technologies in this expanding field. The developed electrofiltration technique makes a valuable contribution to the field by enabling rapid and automated isolation of exosomes from biological fluids, thereby accelerating progress in exosome research. Additionally, this technique has the potential to create a new standard for exosome isolation, benefiting researchers in the rapidly growing field of exosome research.