Assessing the Heating Ability of Carbon Nanotubes-Fe<sub>3</sub>O<sub>4</sub> Nanocomposites for Magnetic Hyperthermia Application

Recently, magnetic nanocomposites have demonstrated considerable potential for applications using magnetic fluid hyperthermia (MFH). The synthesis of hybrid nanocomposites of carbon nanotubes-iron oxide (CNT-Fe 3 O­ 4 ) for radio-frequency hyperthermia therapy and the investigation of their heating efficiency at varying frequencies and field amplitudes of an alternating magnetic field (AMF) are reported. XRD, SEM, EDS, FTIR and SQUID techniques have been employed to fully characterize the as-synthesized samples. XRD and FTIR results confirmed the successful fabrication of the nanocomposites. Magnetization (M) versus magnetic field strength (H) loops at room temperature revealed superparamagnetic behavior with saturation of 17 emu/g. Zero-field-cooled and field-cooled (ZFC-FC) curves showed that the blocking temperature (T B ) was around 282 K. Heating abilities and SAR values as functions of frequency, field amplitude of AMF and concentration of nanoparticles were systematically investigated. Hyperthermia temperatures range can be attained in relatively short times for different concentrations of the nanocomposite. An enhancement in SAR was observed with decreasing concentrations and rising frequency and amplitude. Interestingly, the lowest dose of the nanocomposite (2.5 mg/ml) showed the greatest SAR (113W/g) and intrinsic loss power (ILP) of 1.86 nHm 2 /kg. This elevated ILP value falls into the range achieved by commercial ferrofluids (0.2−3.1 nHm 2 /kg). Lastly, according to linear response theory (LRT), SAR values depend on field amplitude. Overall, the obtained nanocomposites have a significant potential for use in cancer therapies involving hyperthermia, as indicated by their generally good heating efficiencies.