Multiplexed Microfluidics for the Study of Photosynthetic Microorganisms

The ability of large datasets of simple metrics (i.e. growth rate, lipid accumulation) to contribute to the understanding of microalgal photosynthesis is explored in this thesis. Specifically, three tools were developed, (i) a microfluidic multiplexed irradiance assay, which was composed of a microfluidic chip and a liquid crystal display; (ii) a second order mathematical model which can predict the growth under fluctuating light for periods ranging from a day to one under second and; (iii) a combinatorial assay for studying the mixed effect of light and nitrogen on growth and lipid accumulation. The multiplexed microfluidic irradiance assay (Microalgae on display) was capable of producing a large number of independent light treatments (200+), while avoiding the self-shading typical of flask-scale experiments. A set of linear ordinary differential equations were capable of capturing a second order behavior of photosynthetic growth, specifically a penalty at intermediate frequencies. This behavior lies outside the prevailing understanding of a high and low frequency limit. Lastly, the interplay between irradiance intensity and ammonium was resolved, showing that ammonium concentration plays a role at high light intensities only.Ph.D