The efficiency of magnetic hyperthermia and in vivo histocompatibility for human-like collagen protein-coated magnetic nanoparticles

Abstract

Magnetic hyperthermia is a promising technique for the minimally invasive elimination of solid tumors. In this study, uniform magnetite nanoparticles (MNPs) with different particle sizes were used as a model system to investigate the size and surface effects of human-like collagen protein-coated MNPs (HLC-MNPs) on specific absorption rate and biocompatibility. It was found that these HLC-MNPs possess rapid heating capacity upon alternating magnetic field exposure compared to that of MNPs without HLC coating, irrespective of the size of MNPs. The significant enhancement of specific absorption rate is favorable for larger sized nanoparticles. Such behavior is attributed to the reduced aggregation and increased stability of the HLC-MNPs. By coating HLC on the surface of certain sized MNPs, a significant increase in cell viability (up to 2.5-fold) can be achieved. After subcutaneous injection of HLC-MNPs into the back of Kunming mice, it was observed that the inflammatory reaction hardly occurred in the injection site. However, there was a significant presence of phagocytes and endocytosis after the injection of nonconjugated counterparts. The overall strategy to fabricate HLC-MNPs can serve as a general guideline to address the current challenges in clinical magnetic hyperthermia, improved biocompatibility, and enhanced heating characteristics through protein coating.

Gold nanorods together with HSP inhibitor-VER-155008 micelles for colon cancer mild-temperature photothermal therapy

“…These results indicated that PTT combined with VER-M had less recurrence rate than hyperthermia. This results because heatstroke not only directly induces cell injury, but also causes the release of large amounts of inflammatory mediators and cells with extensive biological activities to induce a systemic inflammatory response and immune dysfunction, which has been widely studied 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 . The biocompatibility of the formulation was reflected by the weight change during the treatment.…”

Effect of internal chain-like structures on magnetic hyperthermia in non-liquid media

“…Estimates show that the Zeeman energy μ 0 M s v p H of a magnetite particle with diameter d ∼ 20 nm exceeds the thermal energy kT o if the field H is more than 2 kA m −1 . The typical strength of the magnetic fields used in medical applications lies in the range 2-15 kA m −1 (see, for example, [17,23]). Thus, for the particles with diameter d ≥ 20 nm, in the first approximation, one can neglect the thermal fluctuations of the direction of the particle magnetic moment.…”

“…First, because they are not toxic; secondly, they are relatively cheap; and, next, they have magnetic moments sufficient to provide a link with the magnetic fields easily achievable in the laboratory and clinical conditions. It was concluded in [17][18][19] that particles with a diameter in the range 25-30 nm are most efficient for these applications.…”

Effect of interparticle interaction on magnetic hyperthermia: homogeneous spatial distribution of the particles

“…The typical range of the field, used in the biomedical applications of magnetic hyperthermia, is 2-15 kA m −1 (e.g. [6,10]). Thus, in our analysis we can ignore the fluctuations of the moments' orientations.…”

“…Therefore, during the heating process, the particle moment is transferred across the potential barrier many times and the models, based on the concept of the Neel remagnetization, are quite adequate to meet the physical reality. However, it was shown in experiments [6][7][8] that the particles with diameters of 25-30 nm are the most efficient for magnetic hyperthermia. For these particles, the time of the Neel relaxation is in the range 2.7 × 10 3 − 3 × 10 12 s. Thus, the probability that the particle transfers the potential barrier for half an hour is very low and the concept of the Neel remagnetization, as the main mechanism of the heat production, is not adequate for the physical process.…”