Antibody modified magnetic nanoparticles as a smart cell separation device

Introduction Today, cancer is one of the biggest public health concerns worldwide. Early detection of cancer holds great importance to prohibit cancer cell mutation and drug resistance to treatment. With this concern, using iron oxide (IO) magnetic nanoparticle-based immunomagnetic separation of tumor cells, is one of the highly efficient processes known, subsiding chemo-drugs side effects. This method is focused on magnetic nanoparticles (NP) modified with specific antibodies that helps the single cell detection, by recognizing the over expressed cancer cell surface proteins. Objectives In this study, attachment of EDC/NHS linker to magnetic nanoparticles and antibodies for forming the NP-Ab complex was targeted. In addition, reaching the maximum efficiency of NP-Ab complex with minimum amount of antibody was another purpose of this study. Methods In order to synthesized iron oxide nanoparticles, using the co-precipitation method, 4.5g of FeCl3 and 3g of FeSO4 salts were dissolved in 70°C water, then 20ml of ammonia was added to the solution. The produced IO nanoparticles were activated with EDC/NHS linker, with the ratio of 1:2. Although, the antibody range were determined according to literature, the amount of using Ab in each experiment was assigned based on Design Expert software program. Finally, FTIR and Bradford tests were performed to verify the attachment of IONPs and Ab. Results The DLS and SEM analyses have shown that IO nanoparticles were spherical, hydrophobic, with an average size of 138 nm with 2-4 nm increase after the anti-HER2 conjugation. Also, zeta potential was −36 mV that determined the existence of functional groups on the surface of NPs. ConclusionA highly efficient single cell detection was demonstrated by anti-HER2 modified magnetic nanoparticles. Initial experiments on cells also indicated that target cells were separated successfully. All in all, a bright future for cancer treatment is expected using these smart nanoparticles as a device for early diagnostic of cancer cells

Keywords:

Magnetic nanoparticles , Cell separation , Antibody modified