• Modified Magnetic Nanoparticles for Hepatitis C Virus Genotyping
  • Faezeh Shafie*,1,* Ali Farhadi,2 abbas behzad behbahani,3 Ali mohammad amani,4 Saeed Taghizadeh,5 Gholamreza Rafiei Dehbidi,6
    1. Department of Medical Laboratory Sciences, School of Paramedical Sciences, Shiraz University of Medical Sciences
    2. Diagnostic Laboratory Science and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
    3. Diagnostic Laboratory Science and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences
    4. Department of Medical Nanothechnology, School of Advanced medical science and technologies. Shiraz University of Medical Sciences
    5. Department of Medical biothechnology, School of Advanced medical science and technologies. Shiraz University of Medical Sciences


  • Introduction: Magnetic nanoparticles (MNPs) have been very attractive for scientists and technologists due to their unique physicochemical, optical, and catalytic properties. These properties makes them ideal for widespread biomedical applications such as: magnetic hyperthermia, enhancing magnetic resonance imaging (MRI) data, supplementing tissue engineering efforts and improving the delivery of drugs to difficult to reach microniches. Also, when MNPs bound to target specific oligonucleotide, they can easily separate and detect DNA target upon exposure to an external magnetic field. The aim of this study was to synthesis and characterization of carboxy-functionalized Fe3O4@SiO2-NH2 core shell nonmagnetic carrier for determination of HCV genotypes.
  • Methods: The aminated silica coated MNPs were synthesized by co-precipitation of ferrous and ferric solutions followed by the reaction of TEOS (tetraethoxysilane) and APTES aminopropyltriethoxysilane). Then carboxyl-functionalized silica-coated magnetic nanoparticles (Fe3O4@SiO2-NH2) has been prepared using Succinic anhydride as a cross linker. Finally, EDC/NHS activation agent was used for higher efficient coupling and more stable carboxyl group. The obtained MNPs were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), X-ray diffraction (XRD). Amino modified specific oligonucleotides of HCV genotypes 1 and 3 were designed for the most conserved region (5UTR) of the virus genome and immobilized on surface of prepared MNPs. After hybridization of biotinylated PCR products to genotype-specific DNA probe of HCV, the colorimetric detection were performed using horseradish peroxidase (HRP)-conjugated streptavidin.
  • Results: TEM images analysis showed spherical particles with size range of 20 to 45 nm and an average size of 30 nm with only limited degree of aggregation. The XRD pattern shows that synthesized NPs were highly crystalline in nature. The FT-IR spectra of the functionalized MNPs confirmed the accuracy of synthesis and the functionalization procedures. The sharp peak at 1629cm-1 corresponded to high COOH bond which is required for the attachment of amino modified oligonucleotide to the surface of MNPs was generated. Amplified HCV RT-PCR products were subjected to modified MNPs assay and the results were comparable to the sequencing assay as the gold standard technique for HCV genotyping.
  • Conclusion: This study indicates that the carboxyl functionalization of core shell Fe3O4@SiO2-NH2 MNPs can be used to detect genotypes 1 and 3 of the amplified HCV gene sequences using colorimetric method.
  • Keywords: MNPs, Caeboxl functionalization, HCV, Genotyping