Use this URL to cite or link to this record in EThOS:
Title: Advances in biophysical characterisation through micron scale flow engineering
Author: Saar, Kadi Liis
ISNI:       0000 0004 7961 9286
Awarding Body: University of Cambridge
Current Institution: University of Cambridge
Date of Award: 2019
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Please try the link below.
Access from Institution:
Proteins are the chief actor molecules of cells central to the majority of biochemical and biophysical processes that sustain life. Interactions between proteins and other biomolecules are crucial to a faultless execution of biological function, yet it has remained challenging to analyse these biomolecular interactions with current protein science tools - they commonly rely on non-physiological conditions for performing analysis, thereby compromising the ability to analyse biological interactions. This thesis describes the development and applications of platforms that facilitate rapid analysis of heterogeneous systems of proteins and protein interactions directly in solution, under fully native conditions. I achieved this objective by fabricating micron scale structures, where, in contrast to macroscale systems, chaotic mixing of fluids and the molecules therein was suppressed. In this manner, I was able to dispense with the support structures that prevent mixing in conventional protein analysis platforms and decrease analysis times by orders of magnitude, from hours to seconds. The first part of the thesis was centred around the use of micron scale strategies for probing proteins, protein interactions and protein self-assembly in vitro. First, I demonstrated a platform for performing automated high-throughput measurements on protein self-assembly in a label-free environment. I proceeded by addressing two challenges at the core of creating micron scale separation platforms - the integration of strong and stable electric fields with micron scale channels and the enhancing of the resolution limit of such separation systems. Finally, I devised and demonstrated devices for combined biomolecular separation and analysis, which allowed me to size mixtures of proteins at an unprecedented resolution and gain multidimensional data on biomolecular systems. The second part focussed on probing protein behaviour inside cells. I first described a strategy for detecting intracellular proteins in individual cells in a high throughput manner, offering a substantially advanced multiplexing capability in comparison to existing approaches for analysing intracellular proteins. I then focussed on a specific application of cellular biophysics and measured electrical outputs of cells. This work led to record high power outputs for systems that use biological matter for converting sunlight into electricity. To my knowledge, this was also the first demonstration of a biological solar cell equipped with energy storing capacity, the lack of which had been viewed as one of the most notable limitations of current solar cells.
Supervisor: Knowles, Tuomas Sponsor: Engineering and Physical Sciences Research Council ; European Molecular Biology Organisation
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
Keywords: biophysical chemistry ; protein biophysics ; soft matter physics ; protein self-assembly ; microfluidics ; microdroplets ; microfabrication ; soft-photolithography ; micron scale flow engineering ; micron scale separation approaches ; electrophoresis ; free flow electrophoresis ; single cell proteomics ; biophotovoltaics ; biological solar cells ; biophysics