Executive Summary : | Numerous researcher provided the physical mechanism of heat generation by the superparamagnetic nanoparticles under a high frequency AC magnetic field in magnetic fluid hyperthermia (MFH) application. However to optimized heating efficiency (generally it is measured in terms of Specific absorption rate (SAR)) and the role of intrinsic and extrinsic parameters to modulate relaxation time in general experimental conditions are not yet completely understood. According to Linear response theory magnetic anisotropy plays a key role to enhancing Neel relaxation time. Therefore larger magnetic anisotropy is desirable to increase SAR. It should be noted that the increase in anisotropy doesn't always enhance SAR. In literature, the heating efficiency has been found to increase with low anisotropy. In real time application of MFH , there is a key issue regarding the leakage of MNP from the capillaries of normal tissues, since the particle sizes can be smaller than the pores of the fenestrated capillaries. This can be solved if nanoparticles are clustered to prevent leakage from pores of fenestrated capillaries. Therefore magnetic behaviour of a nanoparticles clusters are strongly influenced by the inter particles interaction or dipolar interaction. Literature suggested that the dipolar interaction in nanoparticles assemblies affected the Neel relaxation time or blocking temperature. Despite the numerous research work was published, there is still some debate on the affect of dipolar interaction on the heating efficiency. Both positive and negative impact on the SAR have been reported. Again the dipolar interaction of dense cluster of nanoparticles in chain like or column like shape creates an additional anisotropy which collectively affect the heating behaviour of the nanoparticles. In this context, SAR of clustered nanoparticles can be understood as a complex interplay between the magnetic anisotropy and dipolar interaction. However, a clear approach to the individual and interplay effect of heating efficiency by the magnetic anisotropy and dipolar interaction is still lacking. In the proposed work we will analyzed the individual contribution of magnetic anisotropy and dipolar interaction affect to enhance self heating response of MNP and also propose to investigate the co-relation between the dipolar interaction and magnetic anisotropy to modulate SAR of MNP. In this work we will proposed to analyzed the affect on SAR by the individual contribution of dipolar interaction and magnetic anisotropy on high magnetized materials like FeCo and FeNi nanoparticles and low magnetized materials like Fe3O4 and MnFe2O4 nanoparticles by coated with different biocompatible materials like Dextran, Chitosen, PEG etc. and in the next work we will try to fixed dipolar interaction and will modulate anisotropy by with different morphology or vice versa in the proposed nanoparticles system to understand the co-relation behaviour to influence heating efficiency. |