ISOLATION AND ANALYSIS OF SINGLE BACTERIAL CELL USING A MICROFLUIDIC DEVICE

Abstract

Tuberculosis (TB) is one of the major reasons of mortality and morbidity worldwide. Its treatment involves a battery of antibiotics to be administered to the patient for 6-9 months. As a result of this prolonged treatment, the mycobacterium undergoes two phases of cell death firstly an initial phase of quick cell death and then a refractory phase of delayed cell death.Due to this refractory phase, some copies among a population of bacteria called as persisters, may develop tolerance or resistance to antibiotics. The persisters are phenotypic variants in the same population. Currently, there is a lack of tools for the in vitro study and analysis of such phenotypic variants as most methods rely on identifying growth and apoptosis in a clonal population. As a result, there is a need for new tools that allows us to isolate and modulate the local environment of individual cells in clonal population to indentify and study the phenotypic variants. Therefore in this dissertation, I have used microfluidic devices as a platform technology for isolating single bacterial cells from a clonal population. These devices also allow us to present the bacterial with various environmental challenges, including treatment with different antibiotics. Finally, I have used fluorescent microscopy to study morphological changes in single E. coli cell upon treatment with different concentrations of kanamycin as a proof of concept of the ability of the microfluidic device platform to analyse single cells.