Physico-chemical and MR relaxometry study of bovine serum albumin-coated magneto-plasmonic nanoparticles designed for potential use in cancer nanotheranostics.

Purpose: In recent years, the use of nanoparticles has been developed to improve MRI contrast. To improve the contrast agents in image-guided therapy by Multifunctional nanoparticles, in this study, we synthesized a theranostic magneto-plasmonic nanocomplex based on magnetic iron oxide nanoparticles and bovine serum albumin-modified gold nanorod (Au@BSA-Fe3O4@CMD). The purpose of synthesizing these nanoparticles was to use them as MRI contrast agent and photothermal agents in in vitro and in vivo experiments.

Materials And Methods: Initially, the properties of the synthesized nanoparticles were investigated by methods such as DLS, TEM, FTIR. MTT assay was used to evaluate the toxicity of nanoparticles. Finally, to evaluate the contrast ability of nanoparticles, MRI images were taken in in vitro and in vivo conditions and then the images were analyzed.

Results: MTT test results on CT26 cell line showed no significant cytotoxicity for Au@BSA-FeO@CMD nanoparticles at concentrations up to 20 ppm. The in vitro results demonstrated that the Au@BSA-FeO@CMD nanocomplex has high T relaxation rate and great relaxivities (r = 140.14 mM s, r = 2.066 mM s, r/r = 67.83). For in vivo conditions, a decrease in T2 signal of 9.64 and 11.01, respectively, was observed for intratumoral and intraperitoneal injection of nanoparticles.

Conclusion: These in vitro and in vivo studies show that Au @ BSA-FeO@CMD nanoparticles can significantly reduce the signal intensity of T2-weight MRI images, and therefore can offer significant potential as a theranostic platform for effective tumor MR imaging.