Cancer has been a constantly escalating threat to human health, affecting millions of people across the globe. In the United States alone, there are nearly 600,000 new cases diagnosed annually, with that number expected to rise in the coming years. Many cancers lack effective treatment methods due to the shear heterogeneity of cancer diseases, necessitating future medicine to become more personalized. Cancer, at its core, is an accumulation of mutations in one's genetic material that leads to uncontrolled cell growth and division. People naturally accumulate genetic mutations as a result of exposure to carcinogenic substances, as well as by innate mechanisms within DNA replication, meaning that cancer is a disease that is essentially inevitable.

In order to attain a more personalized approach to cancer therapeutics, efficient diagnostic and prognostic tools must be developed such that treatable qualities of the cancer can be identified. Circulating tumor cells (CTCs) have garnered attention in this area in recent decades for their unique role in the metastatic process, as well as their potential to act as a prognostic marker. Unfortunately, CTCs exist in such low quantities in the blood that efficient isolation methods have eluded scientists since their discovery.

These experiments seek to establish an inexpensive and efficient method of CTC isolation using antibody-tagged microbubbles. Microbubbles are small, gas filled, lipid monolayers, which have been used for a variety of theranostic applications for their unique acoustic properties, targeting efficiency, and buoyancy. The system proposed in this study seeks to use immuno-microbubbles to capture CTCs from whole blood samples of cancer patients for their quantification and characterization. To this end, a model of the system using fluorescently labeled red blood cells (RBCs) was used to verify the potential of this system to capture a small population of cells from the context of a significantly larger population of unlabeled RBCs.

From our experimentation, it was found that around 72% of labeled RBC could be rescued from a much larger population of unlabeled RBC. The linkage between the immuno-microbubbles and the RBC was verified using microscopy. The recovery rate of RBCs matches or exceeds the current gold standard techniques of CTC isolation. This suggests that the use of immuno-microbubbles to isolate CTCs from patient blood samples is a viable and efficient technique.