Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy.
Results: The XRD analysis indicated the presence of pure Fe3O4-NPs while the TEM images indicated that the Fe3O4-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM study demonstrated that the magnetic properties were enhanced with the decrease in the percentage of honey. In vitro viability evaluation of Fe3O4-NPs performed by using the MTT assay on the WEHI164 cells demonstrated no significant toxicity in higher concentration up to 140.0 ppm, which allows them to be used in some biological applications such as drug delivery.
Conclusion: The presented synthesis method can be used for the controlled synthesis of Fe3O4-NPs, which could be found to be important in applications in biotechnology, biosensor and biomedicine, magnetic resonance imaging and catalysis.
MATERIALS AND METHODS: Here, cellulose fibers (CF) were isolated from rice straw (RS) waste by using an eco-friendly alkali treatment. The CF network served as an anticancer drug carrier for 5-fluorouracil (5-FU). The physicochemical and thermal properties of CF, pure 5-FU drug, and the 5-FU-loaded CF (CF/5-FU) samples were evaluated. The samples were assessed for in vitro cytotoxicity assays using human colorectal cancer (HCT116) and normal (CCD112) cell lines, along with human nasopharyngeal cancer (HONE-1) and normal (NP 460) cell lines after 72-hours of treatment.
RESULTS: XRD and FTIR revealed the successful alkali treatment of RS to isolate CF with high purity and crystallinity. Compared to RS, the alkali-treated CF showed an almost fourfold increase in surface area and zeta potential of up to -33.61 mV. SEM images illustrated the CF network with a rod-shaped structure and comprised of ordered aggregated cellulose. TGA results proved that the thermal stability of 5-FU increased within the drug carrier. Based on UV-spectroscopy measurements for 5-FU loading into CF, drug loading encapsulation efficiency was estimated to be 83 ±0.8%. The release media at pH 7.4 and pH 1.2 showed a maximum drug release of 79% and 46%, respectively, over 24 hours. In cytotoxicity assays, CF showed almost no damage, while pure 5-FU killed most of the both normal and cancer cells. Impressively, the drug-loaded sample of CF/5-FU at a 250 µg/mL concentration demonstrated a 58% inhibition against colorectal cancer cells, but only a 23% inhibition against normal colorectal cells. Further, a 62.50 µg/mL concentration of CF/5FU eliminated 71% and 39% of nasopharyngeal carcinoma and normal nasopharyngeal cells, respectively.
DISCUSSION: This study, therefore, showed the strong potential anticancer activity of the novel CF/5-FU formulations, warranting their further investigation.