Superparamagnetic nanoparticles encapsulated in lipid vesicles for advanced magnetic hyperthermia and biodetection

A multifunctional nanocomposite formed by superparamagnetic maghemite nanoparticles of 12.8 +/- 61.7 nm diameter encapsulated in lipid unilamellar vesicles (i.e., magnetoliposomes) was prepared using size exclusion chromatography (SEC). The quality of the synthesized nanoparticles was characterized by transmission electron microscopy and X-ray diffraction measurements. Using a modified Langevin model, we analyzed the magnetic measurement data. We found that the SEC prepared magnetoliposomes possess superparamagnetic characteristics. We also performed calorimetric based magnetic hyperthermia measurement to quantify field dependent heating efficiency of the obtained magnetoliposomes. A heating efficiency of similar to 160 W/g at 800 Oe and 310 kHz was obtained. Finally, we used magnetoreactance-based biodetection to explore the effect of magnetoliposomes on magneto-impedance (MI) and magneto-reactance (MX) ratios. Compared to pure vesicles, magnetoliposomes were found to increase the MI and MX ratios by similar to 1.0% and 4.5%, respectively. Together, our magnetic hyperthermia and magneto-detection measurements indicate that our SEC prepared magnetoliposomes exhibit good qualities for hyperthermia and biosensing applications. (C) 2016 AIP Publishing LLC.