UCLA

Quantitative phase imaging (QPI) is a label-free microscopy approach using the phase shift of light as it passes through transparent objects, like mammalian cells, to quantify biomass distribution and changes in biomass over time and space. QPI has seen immense interest and advances in hardware and software leading to numerous applications in biology and expansions in utility within the last decades. This dissertation presents a subset of those studies applied to questions of cellular biology and biophysics along with an overview of the QPI field as whole. The initial proportion of this thesis is devoted to modeling and dissecting various biomechanical properties of cellular mechanics including cellular viscoelasticity and work across varying cell types and biological perturbations using purely QPI. This is followed by an in-depth review of the field of QPI including the development and lineages of the various QPI approaches along with the advances in QPI made in the field of cellular biology, biophysics, and diagnostics. Finally, we conclude this thesis with a review of the ongoing technical and biological advances made in QPI along with perspectives on the directions that QPI field maybe proceeding towards. Demonstrating that QPI is not only a robust tool in probing cellular biology and biophysics already but is also expanding its’ capabilities towards more applications in and interrogating fundamental questions about biology.