• Magnetic nanoparticles as a multifunctional theranostic nanoplatform against brain cancer
  • Fatemeh Davodabadi,1 Javad Arabpour,2 Saman Sargazi,3,*
    1. Department of Biology, Faculty of Basic Science, Payame Noor University, Tehran, Iran.
    2. Young Researchers and Elite Club, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
    3. Cellular and Molecular Research Center, Research Institute of Cellular and Molecular Sciences in Infectious,Diseases, Zahedan University of Medical Sciences, Zahedan, Iran


  • Introduction: Therapeutic and imaging agents can be delivered to tumor microenvironments at higher concentrations via nanoscale particles. In addition, if the drug or radiation is delivered precisely and subtly to the cancerous tissue margins, it will not adversely affect normal cells adjacent to the cancerous tissue. As well as improving image quality by reducing noise that would otherwise be present, precise delivery of the contrast agent can also increase the background imaging signal. The background imaging can also be improved as a result of collateral damage. Nanomaterials can be used in molecular imaging techniques to improve the contrast and dispersion of different tissues, improving the sensitivity of the diagnostic tests. Consequently, nanoparticles (NPs) can be defined as tiny, colloidal particles with nanometers. Iron oxide nanoparticles (IONPs) and magnetic NPs (MNPs) have been unveiled as new target-specific contrast agents for magnetic resonance imaging (MRI).
  • Methods: Using the keywords " magnetic NPs", "theranostic", "cancer" and " imaging", we searched PubMed, Web of Science, Google Scholar, and Scopus databases for published studies. Reviews were conducted on articles published.
  • Results: The size of MNPs ranges from 10 to 100 nm. Their retention in the blood is usually long-lasting. Because of their size, the mononuclear phagocytic system cannot recognize them, and they are too large to be removed by the kidney, their extraordinarily long half-life may be the result of their size. Magnetic NPs can be used for many different purposes that extend beyond the generation of hypointense areas on T2/T2*-weighted MR images. Additionally, intravenous administration of these agents can cause their accumulation in tumor tissues, making them antitumor agents. An application of magnetic fields results in a generation of heat or mechanical pressure. As a result of the alteration of the relaxation time of T2, IO-derived contrast agents are frequently used as T2 contrast agents. There are distinct slopes corresponding to r2 and r1 relaxivities in the 1/T2 and 1/T1 relaxation rate plots against Fe concentration. A higher r2*/r1 ratio indicates a better T2* contrast. It is observed that superparamagnetic iron oxide nanoparticles (SPIONs) are almost devoid of magnetism at certain temperatures in the absence of an external magnetic field. As a consequence of their highly elevated magnetism inclination, magnetite and maghemite are considered to be sublime magnetic platforms because of the fact that they can become significantly magnetized when exposed to a magnetic field. A further application of these nanoparticles involves using Fe2O3@Au core and shell nanoparticles as a theranostic agent for brain cancers, such as Fe2O3@Au core–shell nanoparticles designed exclusively for the selective targeting of tumors and real-time guidance of photothermal therapy (PTT). By combining the surface plasmon resonance of au with the magnetic core, a fairly effective contrast agent can be formed under external magnetic fields to serve as a magnetic drug targeting platform. Furthermore, in vivo studies demonstrated that systemic administration of Fe2O3@Au core–shell NPs combined with Magnetic Targeting (MT) and NIR irradiation resulted in complete tumor remission. As a result of the research presented here, Fe2O3@Au core–shell NPs may be an effective and safe approach to developing a targeted PTT strategy for eradicating tumor cells under the guidance of MRI.
  • Conclusion: In the fight against cancer, it has been possible to develop and apply imaging contrast agents and nanovectors for therapeutic purposes. Among the leading approaches under development are magnetic nanoparticles as a way to detect precancerous and malignant lesions and provide concomitant treatment. As a diagnostic tool in both research and clinical settings, magnetic resonance imaging has become a versatile and powerful technique. The use of passive as well as active targeting has shown significant positive results in introducing these agents to tumor cells.
  • Keywords: Magnetic NPs, theranostic, Cancer, imaging,