(65c) Magnetic Blood Purification for Pathogen and Circulating Tumor Cell Removal

The magnetic separation of pathogenic compounds from body fluids is an appealing concept for both improved diagnosis and therapy with prospective applications in personalized medicine. Recently, removal of a diverse array of pathogens has been demonstrated by us and others using extracorporeal dialysis-type devices. Here, we report on the feasibility to remove pathogens and mammalian cells (e.g. circulating tumor cells) from body fluids in a continuous dialysis-type of setting. We employ magnetic nanoparticles functionalized with a newly developed antibody to capture and remove disease-causing factors from the blood.

We assess removal efficiencies from physiological fluids with or without white blood cells using a range of different magnetic bead sizes (50 nm – 4000 nm), concentrations and contact times. Both bacteria and tumor cells can be quantitatively removed from body fluids within acceptable times (1-2 minutes) and bead concentrations (0.2 mg per mL). Then, we exploit the opportunity for rapid and sensitive analysis of the captured entities on magnetic beads recovered from the magnetic separator to allow speedy identification and genetic profiling.

The present theranostic approach could significantly speed up detection and identification of disease-causing pathogens and at the same time provide an effective treatment modality by decreasing the pathogen load to bridge the time before appropriate (patient-specific) drugs can be administered.

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