Magnetic-optical Nanoovals for Capture and Detection of Circulating Tumor Cells in Whole Blood

S. Bhana, X. Huang
The University of Memphis, US

Keywords: circulating tumor cell, magnetic-optical, nanooval, magnetic separation, detection, surface enhanced Raman scattering

Summary:

Sensitive and quantitative detection of circulating tumor cells (CTCs) can provide a powerful tool for cancer early diagnosis, patient prognosis, assessment of tumor stage, monitoring of therapeutic response, and ultimately aiding in optimization of personalized treatment for patient with metastatic cancer. However, CTC detection is challenged by the low number of CTCs in patient blood, as low as few cells in billions of blood cells. We report a new method using novel iron oxide-gold nanoovals (IO-Au NOVs) to simultaneously capture and detect CTCs on-line in whole blood. Compact IO-Au NOVs were synthesized using a seed-mediated growth method. The hybrid NPs were coated with QSY21 Raman reporters and linked with antibodies targeting epithelial cell adhesion molecules (EpCAM) and human epidermal growth factor receptors (HER2) on cancer cell surface. Using CTC-mimic spiked breast cancer cells as a model, we demonstrated that CTCs in whole blood can be captured under a flow condition via magnetic separation, followed by on-line surface enhanced Raman scattering (SERS) detection, with the limit of detection of 1-2 cells/mL blood. Our CTC detection method is simple, rapid, quantitative and ultrasensitive, which may make an important impact in the field of cancer medicine.