Abstract: Objective To develop a novel EGFR aptamer-modified magnetic nanoparticle (Apt-NP) for enhancing the targeted thermal damage to EGFR-positive U251 cancer cells. Method EGFR aptamer was implanted onto nanoparticles via biotin-streptavidin reaction. Apt-NP was characterized by dynamic light scattering (DLS) assay. The binding of aptamer to target cell was evaluated by flow cytometry. The attachment of Apt-NP to target cell was evaluated by Prussian blue staining. Thermal damage under alternative magnetic field was measured by detecting the release of LDH. Results The average size of Apt-NP was 574 nm. Apt-NP could bind with the EGFR-positive U251 tumor cells but not the MDA-MB-231 cell． Importantly，Apt-NP significantly enhanced the thermal damage to EGFR-positive U251 tumor cells but not that to MDA-MB-231 cells. Conclusions Aptamer-modified nanoparticles may have potential utility in tumor targeted thermal therapies．

Key words: Key words: aptamers, thermal therapy, EGFR, Glioblastomas