In vitro and in vivo tumor annihilation by near-infrared photothermal effect of a NiFe2O4/C nanocomposite.

Nanothechnology-mediated photothermal therapy (PTT) is emerging as one of the inspiring alternative modality of cancer therapy that applies near-infrared radiation. High favorability of this approach is due to its minimum invasiveness, safety of non-targeted area, quick recovery, and capable simultaneous imaging. In this approach, photoabsorbing nanomaterials convert energy of infrared light to vibrational motion and generate heat. In the present study, a nanocomposite comprised nickel ferrite and carbon (NiFe2O4/C) was synthesized, characterized and introduced as a novel photoabsorbing agent in cancer phototherapy. NiFe2O4/C was characterized by field emission scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray diffraction patterns. A diode laser of 808 nm with a power density of 1.0 W cm-2 was selected as the light source to evaluate the photothermal property of NiFe2O4/C toward cancer repression in C540 (B16/F10) cell line and melanoma bearing tumor model in male balb/c mice. Temperature enhancement ability of NiFe2O4/C confirmed its photoabsorbing property. While NiFe2O4/C had a concentration dependent cytotoxicity on C540 (B16/F10) cell line, PTT of NiFe2O4/C activated by laser irradiation showed its destroying effect on the C540 (B16/F10) cell line. On the other hand, histological analyses and tumor volume changes were performed for the in vivo PTT of NiFe2O4/C upon intratumoral injection. The results showed that after 24 h, PTT of the nanocomposite cured the tumor properly, whereas NiFe2O4/C injection or laser exposure alone had no treatment effect. Also, 5-day post-treating the melanoma bearing tumor model indicated that the level of necrosis significantly increased during this time in the PTT treated mouse. Therefore, PTT using NiFe2O4/C is proposed as a promising procedure for the melanoma cancer therapy.