Date of Award


Document Type


Degree Name

Master of Science (MS)

Legacy Department



Gao, Bruce Z

Committee Member

Wei , Yanzhang C

Committee Member

Burg , Karen JL


We present the basis of a novel, non-invasive technique for cell diagnostics which utilizes the optical force generated by a weakly focused laser beam to distinguish cells based on their size, structure, composition, and membrane properties. Cell populations of different types, biological states or with different treatments can be studied. This research focuses on two particular instances where other methods of cell sorting, such as those that require fluorescent markers, are not ideal. What's more, this research emphasizes the ability to sort morphologically similar cells that are identical to the naked eye, but phenotypically different on the molecular level. The first study consists of sorting genetically modified cells (Ave. Velocity = 35.5µm/s) from their unmodified phenotype (56.7µm/s). A second study was conducted to show the system's ability to distinguish cancerous cells from one another. Metastatic cancer (50.1µm/s), non-metastatic cancer (21.4µm/s), and healthy (161.7µm/s) murine breast cells were measured to also be significantly different from one another. Thus, a general live-cell analysis technique allowing detection of small cell-based changes or differences, without additional cell manipulation, was developed.