targeted therapy (Patitsa et al. 2016). It is well established that MNP-based therapy

minimizes the side effects of therapy as compared to conventional drug delivery

systems like chemotherapy, radiation, or immunotherapy because of their targeted

approach. Furthermore, these nanoparticles due to their response towards magnetic

field and efficient contrast agents are excellent candidates for magnetic resonance

imaging (MRI) (Hola et al. 2015). These nanoparticles can be made to heat up in

alternating magnetic field, which leads to their application as hyperthermia agents,

conveying thermal energy to tumors, as chemotherapy and radiotherapy enhance-

ment agents (Laurent et al. 2011). Magnetic nanoparticles are excellent candidates

for sensors as they can be remotely and noninvasively employed for imaging probes

and smart actuators. MNPs can also be integrated into the transducer materials and

can be distributed in the samples and removed by magnetic field for active detection

on the surface of biosensors.

The MNPs can be aptly envisioned as the future of medical science as they have

the potential to become valuable tools for therapeutics, diagnostics, and imaging in

the near future. Overall, the research in MNPs will not provide further development

of the medical field but exciting applications of MNPs in related areas. This review

gives an overview of various applications of MNPs in medicine including drug

delivery, magnetic resonance and magnetic particle imaging, sensing, biomarker

detection, antimicrobial agents, and regenerative medicine (Moradiya et al. 2019;

Tay et al. 2018; Richard et al. 2017; Chen et al. 2017). The overall applications of

MNPs are given in Fig. 24.1.

24.2

Magnetic Nanoparticles for Drug Delivery

Drug delivery serves as an alternative therapeutic technique towards the treatment of

different human ailments such as cardiovascular disease, cancer, and microbial-

attacked places (Hola et al. 2015). The concept of drug delivery encompasses

biocompatible approaches and systems for the transportation of therapeutic agents

to the specific site of action in the body. Unlike conventional chemotherapeutic

agents, drug delivery offers the attractive protocol of targeting drug only to the

intended area, thereby reducing the deleterious side effects of the drug to the

surrounding healthy cells or tissues. Moreover, drug delivery overcomes the major

problem of overdosing/underdosing cycle by releasing the drug in a controlled

manner (Mou et al. 2015). For the accomplishment of these goals, the development

of suitable vehicles for drug delivery is of utmost importance that can minimize the

toxic side effects as well as assists in the enhancement of the therapeutic effect. In

this context, MNPs can be harnessed as potent drug delivery vehicles due to their

low cytotoxicity, magnetic attraction, target identification, proper drug uptake and

release, biodegradability, biocompatibility, and reactive surface that can be easily

modified with biocompatible coatings (Kariminia et al. 2016). The drug delivery by

MNPs involves three basic steps: first, the immobilization of a drug in MNPs,

followed by the introduction of the drug/carrier complex into the system/subject,

and finally, the use of high gradient magnetic fields to direct and concentrate the

24

Recent Progress in Applications of Magnetic Nanoparticles in Medicine: A Review

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