Biomedical applications of magnetic nanoparticles

Abstract Magnetic nanoparticles (MNPs) have been a powerful tool in recent biomedical and environmental research. MNPs have widespread uses, ranging from DNA extraction using magnetic bioseparation to hypothermic killing of cancerous cells. Apart from their use in magnetic hyperthermia and magnetic bioseparation, MNPs can be used as drug delivery systems (DDSs). Conventional DDSs are prone to various challenges such as premature release of the drug, off- target delivery, low efficiency in drug loading, and interaction with the natural immune system of human body. Many of these issues can be ameliorated by incorporating MNPs into the DDS, which can be further developed into a magnetic nanocomposite (MNC). These MNCs have better targeting efficiency and higher drug-loading efficacy due to large surface area and are responsive to external magnetic stimuli. As well as improving drug delivery efficiency, these MNCs can be utilized as a theranostics platform to simultaneously diagnose and treat the diseased area. Unique magnetic properties such as low toxicity, high magnetic saturation, and stability in biological solutions make MNPs an excellent choice for targeted drug delivery vehicle and good agents for photodynamic therapy. At the forefront of modern genetic engineering, MNPs are being used in the revolutionary gene editing tool CRISPR-Cas9 system to increase the efficacy of gene editing via increasing gene delivery efficiency. In this chapter we will briefly discuss various aspects of MNPs and their synthesis as well as functionalization of the particles to incorporate them into different MNCs and their biomedical application. We will also discuss the use of MNPs in imaging modalities, which provide an efficient theranostics module against different types of diseases such as cancer.