Abstract: This study were to explore the preparation technology conditions of fucoidan-selenium nanoparticles (FD-SeNPs),and to further characterize their structure and investigate their inhibition effects on tumor cells growth.Using fucoidan (FD) as a template,ascorbic acid (Vc) was used to reduce sodium selenite (Na₂SeO₃) to prepare FD-SeNPs,and the process parameters were optimized by single factor design and response surface experiments.Fourier transform infrared spectrometer (FT-IR),scanning electron microscope (SEM),energy dispersive X-ray spectroscopy (EDX),transmission electron microscope (TEM) and X-ray diffraction (XRD) were used to characterize its structure.The MTT method was used to determine its effect on the survival rates of HepG2 hepatoma cells and A549 lung cancer cells.The results showed that the optimal conditions of FD-SeNPs were list as follows:the reaction time of 1 h,the reaction temperature of 35 ℃,molar ratio of Vc to Na₂SeO₃ of 14∶1,and FD concentration of 0.8 mg/mL.Under these conditions,the FD-SeNPs with particle size of (83.4 ± 0.55) nm,Zeta potential of (-31.89 ± 0.47) mV and selenium content of 29.93 % was obtained.After identification,its surface morphology was uniform spherical,which was composed of 77.59% Se,17.70% C and 3.41% O elements.The results of MTT assay showed that FD-SeNPs could significantly inhibited the proliferation of HepG2 cells and A549 lung cancer cells,and had a good dose effect.The above results showed that the FD-SeNPs had been successfully prepared and exhibited certain inhibitory effects on tumor cells growth,which provided a certain technical means and theoretical data reference for the application and development of anti-tumor clinical drugs.

Key words: fucoidan, selenium nanoparticles, structural identification, inhibition effect on tumor cells growth