linkages on the hydrogel matrix allows simplistic design of a multifunctional

nanoplatform as the MRI-guided drug delivery system (Su et al. 2019). Nosrati

et al. synthesized two different amino acid (L-lysine and L-phenylalanine)-modified

Fe3O4 NPs. The authors revealed that the modified MNPs worked well as contrast

agents in the early diagnosis of tumor cells using MRI. Also, these modified MNPs

provide a suitable and appropriate system for delivery of anticancer drug (curcumin)

to breast cancer cells (Nosrati et al. 2018b).

24.6

Magnetic Nanoparticles for Hyperthermia Treatments

Hyperthermia is a conventional noninvasive method for the treatment of cancer with

the aid of high temperature (Obaidat et al. 2019). When the cancerous cells exposed

to high temperature (above 41
C), fluidity and the permeability of the cell mem-

brane increases whereas the rate of production of nucleic acid and protein decreases.

The exposure to high temperature induces protein denaturation and ultimately

destructs cancerous cell. However, extensive heat is required to be applied that

may cause negative effects on healthy tissues. Thus, to overcome these side effects,

plentiful heat must be transferred only to the targeted cells, i.e., tumor cells.

Magnetic hyperthermia (MH) employs the MNPs which produce heat in the local

region of the tumor cells through vibration or rotation stimulated by altering

magnetic field (AMF). Thus, MH overcomes the drawbacks of local hyperthermia

where heat is transferred directly to the cancerous cells thereby minimizes the side

effects and allows for deeper penetration to cancer cells. For practical applications of

MNPs in MH, nanoparticles must possess sufficiently large Ms that will produce

enough heat in cancer cells upon exposure to AMF. Besides large Ms, another

requisite is that the MNPs should be superparamagnetic so that in the absence of

the external magnetic field, MNPs lost their magnetism and thus ensure their

colloidal stability. Amongst the various available MNPs, superparamagnetic iron

oxide nanoparticles such as magnetite (Fe3O4) and maghemite (γ-Fe2O3) are very

popular candidates to be used for MH applications because of their good magnetic

properties, ease of commercial availability, biocompatibility, and biodegradability.

The magnetic properties of these MNPs can be tailored by (1) varying the method of

synthesis, (2) changing the size and shape, and (3) modifying the surface

functionalizing moieties. Kubovcikova et al. made use of poly-L-lysine to improve

the stability and biocompatibility of Fe3O4 nanoparticles. The modified MNPs were

subsequently attached with the specific antibodies for the detection of tumor cells

mediated by the antibodies. The results have confirmed the potential of the

synthesized nanoparticles for the combined detection of the antibody-derived

tumor cells and their therapy in combination with MRI and hyperthermia

(Kubovcikova et al. 2019). Ramos-Guivar et al. synthesized completely nontoxic

low-cost maghemite (γ-Fe2O3) nanoparticles embedded in a nanohydroxyapatite

matrix to study their potential for the MH application. MH experiments have

shown that the heating response tends to increase by increasing concentration of

the modified MNPs in water (Ramos-Guivar et al. 2020). Recently, Soleymani et al.

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