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Microfluidic Techniques for Protein Detection and Manipulation


Type

Thesis

Change log

Authors

Chiu, Hoi Kei 

Abstract

Protein-protein interactions are of central importance in biological systems. The interplay between proteins determines the functioning of such systems. Accordingly, a variety of methods have been established for the study of protein-protein interactions, but each class of methods has key limitations. In particular, dissociation constants of biologically relevant interactions are often in the nM to μM range, probing at such low concentrations requires highly sensitive techniques. An improved understanding of the functioning of proteins lead to increased drug usage in combating diseases. Bio-compatible and bio-degradable drug-carrying vehicles are highly desirable. This thesis describes the unique properties of fluids when confined to small length scales, which enable analysis of proteins at low concentrations and manipulation of protein assembly for the manufacture of function materials. The analysis on protein-protein interactions evolved around the differences in hydrodynamic radii of proteins in the monomer and bound states, which change the diffusion constants of the protein. By employing a non-specific label, the rate of diffusion of various proteins can be detected. An existing microfluidic platform was initially employed to investigate biologically important interactions, yet detection limit and precision still posed as problems hindering measurements. A versatile, universally-applicable chemiluminescent platform for protein detection was introduced in this thesis. The intrinsically low background noise from chemiluminescence provides a low detection limit where tight-binding interactions or low concentration samples can be easily analysed. Lastly, microdroplets fabricated using two immiscible aqueous systems offer high bio-compatibility, and thus, when cross-linked with protein fibrils, would serve as optimal vehicles for drug delivery or cell encapsulation purposes.

Description

Date

2018-10-08

Advisors

Knowles, Tuomas

Keywords

Microfluidics, Protein detection, Chemiluminescence, Emulsions

Qualification

Doctor of Philosophy (PhD)

Awarding Institution

University of Cambridge