Preparation Of Nanoprobe Tf-USPION And Its Application Study In Prostate Cancer

Objective:To synthetize multifunctional probe transferring-ultrasmall superparamagnetic iron-oxide nanoparticle(Tf-USPION),characterize various physicaochemical properties and research its applications in targeting magnetic resonance imaging(MRI)and photothermal therapy(PTT)for prostate cancer.Method:(1)USPION was synthesized by a solvothermal method,and Tf-modified-USPION was prepared through EDC/NHS reaction.(2)To characterize physicaochemical properties of the nanomaterial used X-ray powder diffraction patterns(XRD),transmission electron microscopy(TEM),a vibrating sample magnetometer(VSM),the transverse T2 relaxation time,fourier transform infrared spectra(FTIR),ultraviolet-visible-near infrared spectra(UV-vis-NIR),and photothermal performance analysis.(3)The cytotoxicity of the nanoparticles was estimated via a cellular methylthiazolyldiphenyl-tetrazolium(MTT)assay after incubated with PC3 cells.(4)PC3 cells were incubated with PBS,USPION,and Tf-USPION.Then MR scanning was performed to get in vitro imaging evaluation.(5)PC3 cells were incubated with PBS,Tf,USPION,and Tf-USPION in a 96-well culture plate.Then the cells were exposed to 808 nm 8.3 W/cm2 laser for 5 and 10 min.The viability of cells was detected by MTT assay.In addition,cell viability was also examined using Calcein AM and PI staining method,after PC3 cells treated as above and exposed to a laser 10 min.(6)For verifying the tumor-targeted MRI effects,atumor bearing mouse was administered with nanaoprobe Tf-USPION by tail vein injection.MR scanning was performed before and after the intravenous administration.Result:(1)The USPION was successfully prepared by a simple one-step solvothermal method.The molecular probe Tf-USPION was acquired after as-prepared USPION conjugated Tf using coupling agents(EDC and NHS).(2)XRD confirmed the main constituent of Fe3O4.USPION was uniform distribution with an average crystallite size of about 6 nm by TEM.The saturation magnetization was 25.2 emu/g.The composite was confirmed by FTIR.The relaxation rate of Tf-USPION was 33.08 mM-1S-1.The UV-vis-NIR absorption at different concentration was shown considerable absorption from 700 nm to 1000 nm.A rapid temperature increase of the Tf-USPION solution showed as soon as exposed and the temperature enhanced by 41.5? at 0.5mg/mL for 4 min,while H2 O solution was only raised by 7.0 ?.(3)MTT assay showed that even at a concentration of 0.8mg/m L,the cells remained reach 107.00%,indicating the biosafety for further applications.(4)MRI in vitro revealed the Tf-USPION and USPION treatment groups showed significantly reduced signals in comparison with the cells treated with PBS.And the Tf-USPION treated cells showed a significantly darker image and decreased relaxation times compared with the USPION treated cells.(5)MTT assay of PC3 cells PTT showed approximately 20.85% and 16.61% cells treated with molecular probe Tf-USPION survived under laser irradiation for 5 or 10 min.Furthermore,Calcein-AM and PI stained cells were observed under an inverted fluorescence microscope and luminescence images were showed the PC3 cells treated with Tf-USPION under a laser irradiationcaused significant cell death.(6)Tumor xenograft model was successfully established.The signal intensity of tumor tissue gradually decreased after injection with Tf-USPION and can last for a long time.Conclusion:We report a facile approach to synthesize nanoprobe Tf-USPION with good biocompatibility,MR molecular imaging ability and better photothermal conversion efficiency.Tf-USPION exhibited good MR imaging and PTT on prostate cancer cells,and prostate cancer had been successfully targeting MRI in vivo,which providedan ideal candidate for simultaneous early diagnosis and PTT of prostate cancer.