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Global Translational Medicine SPION for cancer theranostics

on Cancer, 20 million new cancer cases were diagnosed by the absence of hysteresis, showing no remanence
worldwide, resulting in 9.7 million cancer-related fatalities. or coercivity and enabling the material to be used as a
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Among all cancer types, lung cancer remains the most contrast agent for MRI, a widely used medical imaging
diagnosed, representing 12.4% of all cancer diagnoses, tool. Under the influence of a magnetic field, SPION-based
followed by breast cancer, which accounts for 11.6% of total materials exhibit strong paramagnetic behavior, with high
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cases and is the most commonly diagnosed cancer among susceptibility and saturation magnetization. SPION-
women in both developed and developing countries. In based systems can be further enhanced to deliver a variety
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India alone, more than 1.41 million new cancer cases were of cytotoxic anticancer drugs (e.g., doxorubicin [DOX]
reported in 2022, with carcinoma responsible for 910,000 and docetaxel) specifically to tumor sites using an external
deaths and breast cancer being the leading cause of death. magnetic field while minimizing side effects on healthy
These statistics highlight the limitations of current cancer tissues. 12-14 Furthermore, SPION-based magnetic systems
treatment modalities and underscore the need for the can induce heat when exposed to an external magnetic
development of early cancer detection and more effective field, making them a potential candidate for magnetic
therapeutic approaches. hyperthermia (MHT) treatment, a promising tool for
localized tumor ablation. The versatility of SPION-based
Despite the use of multimodal treatment strategies – systems makes them highly efficient in serving a dual
including surgery, radiation therapy, and chemotherapy – purpose in cancer theranostics.
that improve outcomes in patients with locally advanced
cancer, chemotherapy remains the primary option once According to the literature, various synthesis strategies,
6,7
cancer cells begin to metastasize. However, conventional such as coprecipitation, hydrothermal/solvothermal
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chemotherapy has significant disadvantages, particularly methods, thermal decomposition, sonochemical
the severe adverse effects it causes in patients. As a result, techniques, and microemulsion methods, have been
one of the most challenging aspects of cancer treatment used to prepare high-quality SPIONs. However, SPIONs
is delivering anticancer drugs to cancer cells while without proper surface modification tend to aggregate,
minimizing damage to healthy tissues. Similarly, traditional which reduces both their magnetic properties and colloidal
imaging modalities, such as magnetic resonance imaging stability, limiting their application in magnetic targeting,
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(MRI) and X-ray computed tomography, also have MRI, and hyperthermia. By introducing appropriate
inherent limitations due to the use of radioactive materials, surface modification strategies, such as organic or inorganic
high costs, low sensitivity, and limited tissue penetration coatings, it is possible to enhance their biocompatibility
depth. Given these drawbacks, novel and more efficient and colloidal stability, preventing particle agglomeration
theranostic strategies incorporating highly sensitive probes and improving targeting capabilities. As per the literature,
must be developed for early and precise cancer detection. various synthesis strategies such as coprecipitation,
hydrothermal/solvothermal, thermal decomposition,
In this context, nanomedicine has emerged at the sonochemical, and microemulsion techniques have been
forefront of cancer research due to its potential to provide used to prepare high-quality SPIONs. However, SPIONs
a comprehensive theranostic approach, significantly without proper surface modification can have a tendency
impacting the global economy. Various nanostructures, to aggregate by reducing both magnetic properties
2-4
such as polymeric liposomes, gold (Au) NPs, and SPIONs, and colloidal stability by limiting their application in
have been reported for target-specific drug delivery magnetic targeting, MRI, and hyperthermia. However, by
systems. 9-11 In particular, chemotherapeutic agents with introducing appropriate surface modification strategies,
poor solubility and less absorption capacity are encapsulated such as organic or inorganic coatings to the surfaces
or integrated into these nanostructures. However, the of SPIONs, one can enhance the biocompatibility and
effectiveness of these NPs in drug delivery applications colloidal stability by preventing particle agglomeration
depends on their shape, size, and other biophysical and as well as targeting capabilities. Furthermore, the
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chemical properties. A comparison table of different incorporation of other NPs, such as Au and Ag, can further
NP-based formulations is provided in Table 1. Although all enhance the functionality of SPIONs and expand their
nanostructures have both advantages and disadvantages, range of applications. For instance, integrating Au NPs
SPION-based nanostructures offer a versatile platform for can provide plasmonic features to SPIONs, making them
loading various chemotherapeutic agents, enhancing the a promising candidate for both MRI and photothermal
effectiveness of cancer treatment. At room temperature, therapy. Similarly, the integration of Ag NPs imparts
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SPIONs exhibit superparamagnetism when the particle antimicrobial properties, broadening the biomedical
size is smaller than 30 nm. When the applied external applications of SPIONs. Moreover, proper surface coatings
magnetic field is removed, this property is characterized on SPIONs create multifunctional nanoformulations that

Volume 4 Issue 2 (2025) 32 doi: 10.36922/gtm.8464