# Magnetic Nanomaterials for Magnetically-Aided Drug Delivery and Hyperthermia
## 9 Drug Delivery  
Drug delivery using magnetic nanoparticles has become a very popular topic due to the enhancement of performances in therapeutic drugs and their delivery to the targeted locations without side effects. Commonly, antibodies, chemotherapeutic drugs, and other disease-associated drugs are bound to the magnetic nanoparticles, and are directed to the targeted diseased areas in the human body [23]. Researchers have been studying the use of magnetic nano- and micro-materials for targeted drug delivery since the late 1970s. It has been noted that [PERSON] and co-workers in 1996 did a Phase 1 clinical trial of magnetically targeted drug delivery for the first time [4]. Since then, different research groups have been using different strategies to synthesize magnetic drug carriers for drug delivery. Magnetic nanoparticles loaded with doxorubicin were produced by FeRx, Inc., (Wheat Ridge, CO, USA) [1; 81]. TargetMAG-doxorubicin nanoparticles involving a multidomain magnetite core  
Figure 7: TEM (**1a,1b**) and HRTEM (**1c**) images of Fe/Fe\({}_{3}\)O\({}_{4}\)-core/shell nanoparticles that are forming the inorganic core of the nanoplatforms for protease detection [79]. With permission from [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON]; [PERSON], Nanoplatforms for highly sensitive fluorescence detection of cancer-related proteases. _Photochemical & Photobiological Sciences_**2014**, _13_ (2), 231–240. Copyright Royal Society of Chemistry, 2014.  
and a cross-linked starch matrix with terminal cations are currently commercialized by Chemicell GmbH, Berlin, Germany [82]. Alnis Biosciences, Berkely, CA, produces a magnetic nanoparticle hydrogel, which comprises chemotherapeutic agents, Fe oxide colloids, and different types of targeting ligands [83]. There are several good reasons to use nano-biotechnology in drug delivery such as its capability of targeting more specific drugs, biocompatibility, safety, and less toxicity. There are major factors that need to be considered when designing carriers for drug delivery. The incorporation of the drug to the carrier, stability, biocompatibility, biodistribution, targeting, and drug release, are just a few of them. It is very important to know the biodegradability of the nanoparticles, and the effect of residual materials as well. The main advantages of magnetic nanoparticles are high surface-area-to-volume ratios so it is easy to attach a large number of therapeutic molecules, and the magnetic properties of nanoparticles help to image the drug delivery through MRI [84]. As stated above, magnetic nanoparticles have been used as chemotherapeutic drug carriers. At the same time, MNPs have been used to carry drugs such as doxorubicin, methotrexate [85] by attaching or encapsulating. [PERSON] and co-workers have discovered the synthesis and release characteristics of magnetic PECA nanoparticles as drug carriers for targeted delivery [86]. In this study, magnetic poly(ethyl-2-cyanoacrylate) (PECA) nanoparticles containing anti-cancer drugs (Cisplatin and Gemcitabine) were prepared by inter-facial polymerization. It was also found that the amount of Cisplatin in MNPs is higher compared to the Gemcitabine. The reason is due to the hydrophobicity of Cisplatin. It has a high solubility in the oil phase and is well encapsulated in MNPs [86]. [PERSON] and co-workers developed magnetic nanoparticles coated with poly((2-dimethylamino) ethyl methacrylate) (PDMAEMA) for drug delivery and release [87]. These Fe\({}_{3}\)O\({}_{4}\)/PDMAEMA nanoparticles contain a core/shell structure and capable of loading drugs into the polymer shell. By altering the pH, the release rate of the drug can be effectively controlled [87]. They have synthesized nanoparticles with biodegradability, superparamagnetism, and fluorescence as well [88]. They used an external magnetic field to deliver the drug-loaded nanoparticles to the target organs. The release of the drug at the targeted location was slow and steady [88].