However, the neighboring healthy tissues may also be injured by the redundant heat. It is proved that the heat generation efficiency of MNPs heavily depends on the particle size and frequency of external AMF [7, 9]. As the particle size increases to micron-sized or AMF frequency decreases, the degree of Néel relaxation and Brownian relaxation decreases, suppressing heat generation. Meantime, AMF-induced vibration or rotation of particles displaces heat generation as the main pattern of AMF energy consumption. In selleck inhibitor a newly reported research, magnetic microdiscs were used for targeted cancer cell destruction by means of AMF-induced vibrations [10].
In theory, the MNPs reorient in the alternating magnetic field [11] and the oscillation of Crenolanib datasheet immobilized MNPs takes place in situ in the localization of cancerous tissues [12]. Hence, the oscillating MNPs can mechanically damage cancerous
tissues at the cellular level as ‘nanoscale scalpel’. It is notable that no thermal damage will be made to the surrounding tissues. The utilization of forced vibration of MNPs makes the best use of the neglected part of AMF energy consumption. In biomedical applications of forced MNP vibration, patterns and intensity of MNPs’ vibration, as well as the degree of thermal damage, will vary according to differences in size, morphology, and exposure concentration of MNPs. By now, most biomedical application research of MNPs related to nanospheres [13]. However, the involvement
of rod-shaped MNPs (rMNP) is greater than that of spherical MNPs (sMNP). In this research, an assumption that AMF-induced oscillations of rMNPs can damage cell viability more seriously will be investigated in vitro on human cervical carcinoma cells (HeLa), considering their extensive use in cells uptake and tumor therapy research [14–16]. Similarly sized rod-shaped (length 200 ± 50 nm, learn more diameter 50 to 120 nm) and spherical (diameter 200 ± 50 nm) Fe3O4 MNPs in three different concentrations were synthesized and used to investigate the effects of MNP morphology and concentration in killing tumor cells. Methods Synthesis of MNPs Spherical Fe 3 O 4 MNPs FeCl3 · 6H2O (0.81 g) was dissolved in 25 mL glycol and transferred to a 50-mL teflon-lined stainless steel autoclave. KAc (1.47 g) was then added to the solution, stirring Gefitinib in vitro constantly. Autoclave was sealed and maintained at 200°C for 24 h. After naturally cooled to room temperature, the black magnetite particles were gathered by magnet and washed with deionized water and ethanol three times, respectively. The final product was dried in a vacuum at 60°C for 12 h. Rod-shaped Fe 3 O 4 MNPs Rod-shaped MNPs were synthesized following the procedure described previously [17]. Stoichiometric FeSO4 · 7H2O (0.139 g), FeCl3 · 6H2O (0.270 g), and 5 mL ethylenediamine were sealed in the autoclave and maintained at 120°C for 12 h.