Simple and efficient capture of EGFR-expressing tumor cells using magnetic nanoparticles

Abstract

Capturing tumor cells has attracted the attention because such cells can be used for diagnosing the occurrence and progression of cancers. Here we present a simple and efficient capturing of tumor cells using anti-EGFR antibody-conjugated magnetic nanoparticles. EGFR is a well-established epithelial cancer-specific marker that is over-expressed in many types of tumor cells. The conjugation of an anti-EGFR antibody with magnetic nanoparticles through a PEG-linker was shown to be highly efficient for preventing the non-specific binding of cells and improving the stability of the resulting nanoparticles even at a high salt concentration. The use of EGFR-targetable nanoparticles resulted in about 57% capture efficiency in 20 min for two cancer cell lines, PC9 (lung cancer) and HeLa (cervical cancer). The survival rate of the captured cells was approximately 85%, and most of the cells were retrievable, providing options for a further analysis of captured cells such as a mutational investigation of EGFR-related cancers. The present approach can be used for capturing circulating tumor cells (CTCs) expressing EGFR and the subsequent diagnostic analysis of the captured cells.