An easily prepared ferrofluid with high power absorption density and low cytotoxicity for biomedical applications

A Ferrofluid with Surface Modified Nanoparticles for Magnetic Hyperthermia and High ROS Production

“…Concerning the VSM measurements, which are obtained under room temperature conditions, the hysteresis loops of the samples of uncoated and coated MNPs are displayed in Figure 4a. The magnetic saturation observed for coated MNPs (M s_coated = 34 emu/g) is approximately 50% less than the uncoated MNPs (M s_uncoated = 70 emu/g), and this intensity is very similar to that obtained for other coated MNPs, in which some catechol derived compounds have also been used [16,17]. Additionally, by analyzing the hysteresis loop of Figure 4a, non-significant differences are measured in the remanence M r_coated = 1.7 emu/g and the reached coercive field (H c_coated = 10 Oe) is 50% diminished.…”

“…In Figure 2b, the histogram is shown using n = 300 MNPs, in which the central value of each bar is fitted to a Gaussian distribution function, reaching σ = 13.5 ± 5 nm. This diameter size is slightly larger than the crystal size measured by XRD, also some polydispersity of the particle sizes is observed, but this non-uniformity is the expected behavior due to the synthesis method of co-precipitation [16,17,24]. to a Gaussian distribution function, reaching σ = 13.5 ± 5 nm.…”

“…to a Gaussian distribution function, reaching σ = 13.5 ± 5 nm. This diameter size is slightly larger than the crystal size measured by XRD, also some polydispersity of the particle sizes is observed, but this non-uniformity is the expected behavior due to the synthesis method of co-precipitation [16,17,24]. Concerning TGA measurements, Figure 3a displays the mass loss of uncoated and coated MNPs while the temperature is continuously increased.…”

“…During three months of observation, no sedimentation of the coated MNPs was able to be observed (at room temperature). In contrast, for pH = 7 and 4.5, the intensities are 26 mV and 21 mV, respectively, which involves a moderated (but adequate) colloidal stability [17]. Thus, the coated MNPs are dispersed in the liquid medium and after 2 h they are partially precipitated without clusters forming.…”

“…In the field of magnetic hyperthermia (MHT) for cancer therapy, dopamine is one of the catechol-derived coatings that has been frequently used [14][15][16]. Recently, an easily prepared ferrofluid using dopamine coated MNPs has been reported [17], which has not only very low cytotoxicity but also a high power absorption density. In that work, good cancer therapy results are obtained in vivo experiments.…”