roghayeh soltani naseri

In this research, core-shell SiO2/SnO2, SnO2/SiO2 composite nanofibers, and SnO2 nanofibers were synthesized by electrospinning method and were calcined in an electric furnace at temperature of 500 degrees Celsius for 2 hours. Photocatalytic degradation ability of synthesized nanofibers was studied on Crystal violet, methylene blue and methyl orange dyes under ultraviolet light. Structural characteristics of core-shell SnO2/SiO2 nanofibers, SiO2/SnO2 and SnO2 nanofibers were investigated using field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), X-ray diffraction spectroscopy (XRD), and Fourier transform infrared spectroscopy (FT-IR), energy diffraction X-ray spectroscopy (EDX) and Xmap analysis. TEM images clearly show the core-shell structure of SiO2/SnO2 and SnO2/SiO2 nanofibers with an average diameter of 550 nm. XRD analysis shows the amorphous structure of nanofibers before thermal treatment and the formation of the dominant crystalline phase after thermal treatment. Uniform distribution of elements was observed by Xmap analysis. The comparison of photocatalytic decomposition of methylene blue, methyl orange and crystal violet dyes in the presence of SnO2 single layer nanofibers, core-shell SnO2/SiO2 nanofibers and SiO2/SnO2 shows that core-shell SiO2/SnO2 nanofibers with 40.58 percent decomposition in methylene blue, 44/44 in methyl orange and 12/31 in crystal violet had the most effect in destroying colors.

Doxorubicin (DOX), which is used to treat malignant cancerous tumors, has a high toxicity that by controlling the release of the drug into tumor cells, at the right time and place, the toxicity of the released drug and its side effects can be reduced. In this study, we investigated the release of doxorubicin from SiO2/DOX nanofibers in vitro. Electospun synthesized nanofibers from SiO2/DOX nanoparticles, were used to investigate the release of doxorubicin anticancer drug. X-ray diffraction (XRD) technique showed amorphous structure for nanofibers. According to field emission scanning electron microscopy (FESEM) images, the diameter and approximate length of the synthesized nanofibers were 300-400 nm and several tens of micrometers. Based on the analysis of X-energy diffraction (EDX) spectroscopy, the amount of silicon, oxygen, carbon, nitrogen and chlorine in the samples were: 30.18, 31.84, 29.83, 4.41, and 3.75 percent in the samples, respectively. Xmap analysis showed the homogeneous distribution of silicon, oxygen, carbon, chlorine and nitrogen atoms in nanofibers. Functional species and chemical bonds of nanofibers were detected by FT-IR analysis and showed that silicon has peaks at 1090, 804 cm-1 are related to asymmetric tensile, symmetric tensile vibrations at the Si–O–Si bond. Moreover, vibrations of Si–OH were appeared in the range of 3200 and 3600 cm-1. Drug release to applicant synthesized nanofibers, was investigated in vitro at 37 °C and pH=5.4. As a result, the produced nanofibers have the best and longest release time at pH=5.4 and can be used as drug carriers in targeted treatment anticancer drugs.