Polymeric Nanomagnets for releasable capture of tumor cells

A. Singh, M.M. Amiji
Northeastern University, US

Keywords: SPION, CTCs, polymeric particles, targeting, EGFR

Summary:

The aim of this work has been to devise a multifunctional target-specific magnetic nanoparticle (t-MNPs) system to capture cells in vitro from blood, plasma, saliva and other body fluids, their purification using external magnetic field, followed by their subsequent release by competitive binding. Oleic acid capped hydrophobic SPION nanoparticles were successfully encapsulated in PCL particles and PCL-SPION particles were further coated with gelatin followed by borohydride reduced gold nanoparticles. The gold-thiol chemistry was employed to functionalize the gold coated surface with EGF receptor targeting peptide for targeted capture of EGFR overexpressing cancer cells. Luciferase expressing PanC-1 cells were chosen as the model cell system for our study though these nanoparticles can be used for any other EGFR overexpressing cell line. Our results successfully establish that these particles are capable in capturing a few hundred cells/mL of blood. Most importantly, the t-MNPs are able to harvest and subsequently release the target cells through a competitive binding based approach. Glutathione was used as a competitive ligand to disrupt the EGFR targeting peptide’s linkage to the gold nanoparticles, thereby releasing the particle from the captured cell surface.