No abstract

Superparamagnetic cobalt ferrite nanoparticles (CoFe 2 O 4) possess favourite advantages for theranostic applications. Most of previous studies reported that CoFe 2 O 4 magnetic nanoparticles (MNPs) are suitable candidates for induction of hyperthermia and transfection agents for drug delivery. The present study synthesized and investigated the potential use of CoFe 2 O 4 as a contrast agent in magnetic resonance imaging (MRI) by using a conventional MRI system. The CoFe 2 O 4 were synthesized using co-precipitation method and characterized by TEM, XRD, FTIR, EDX and VSM techniques. Relaxivities r 1 and r 2 of CoFe 2 O 4 were then calculated using a 1.5 Tesla clinical magnetic field. The cytotoxicity of CoFe 2 O 4 was evaluated by the MTT assay. Finally, the optimal concentrations of MNPs for MRI uses were calculated through the analysis of T 2 weighted imaging cell phantoms. The superparamagnetic CoFe2O4 NPs with an average stable size of 10.45 nm were synthesized. Relaxivity r 1 , 2 calculations resulted in suitable r 2 and r 2 / r 1 with values of 58.6 and 51 that confirmed the size dependency on relaxivity values. The optimal concentration of MNPs for MR image acquisition was calculated as 0.154 mM. Conclusion: CoFe 2 O 4 synthesized in this study could be considered as a suitable T 2 weighted contrast agent because of its high r 2 /r 1 value. 2 Material and methods 2.1 Materials Co (II) and Fe (III) were purchased from Aldrich, Scharlau and Alfa Aesar. NaOH was obtained from Merck. MTT (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium Bromide) was purchased from Sigma Aldrich. Agarose gel and deionised water (DI water) were used during the tests. 2.2 Preparation of CoFe 2 O 4 MNPs CoFe 2 O 4 MNPs were synthesised by co-precipitation method in an alkaline aqueous environment. The reaction mixture was prepared from iron sulphate (Fe 2 (SO 4) 3 salts) and cobalt chloride (CoCl 2 salt) with 0.1 M concentration of metal salts. All components of the reaction mixture were deoxygenated with nitrogen gas before mixing. In the next step, 5.0 M NaOH solution was added with vigorously stirring of mixing reaction until reaching a pH of 12.4. The obtained solution was then replaced while stirring at 80°C for

The conjugate does not cause any enhancement of radiation efficiency on MeL-Rm cell line. With regards to PDT, we found that the conjugate induced cell death at twice the rate when compared with 5ALA alone. Therefore, the conjugate can be an appropriate delivery agent for 5ALA and may also enhance the destruction of tumor cells. Finally, comparing the two types of treatment shows that PDT is a more efficient treatment for this cell line.

Nanotechnology and ALL.