Umbelliprenin-coated Fe3O4 magnetite nanoparticles: Antiproliferation evaluation on human Fibrosarcoma cell line (HT-1080)

The potential applications of Fe3O4 magnetite nanoparticles (MNPs) in nanomedicine as drug delivery systems are well known. In this study we prepared umbelliprenin-coated Fe3O4 MNPs and evaluated the antiproliferative effect of combination in vitro. After synthesis of Fe3O4 MNPs, particles were characterized by transmission electron microscopy, energy-dispersive spectroscopy, and X-ray diffraction spectroscopy techniques. The natural candidate compound — umbelliprenin— was isolated and identified and umbelliprenin-coated Fe3O4 MNPs were prepared, using precipitation method. The surface chemistry of umbelliprenin-coated Fe3O4 MNPs as well as their thermal decomposition characteristics was examined using Fourier transform infrared spectroscopy and Thermogravimetric Analyzer equipment, respectively. HT-1080 cells were cultured until the logarithmic phase of growth, and MTT assay was successfully carried out to evaluate the possible cytotoxic effects of umbelliprenin-coated Fe3O4 MNPs in viable cells in vitro. The results demonstrated that umbelliprenin has moderate antiproliferative effects with IC50 value of 50 μg/mL. However, the combination of umbelliprenin and Fe3O4 MNPs showed the IC50 value of 9 μg/mL. In other words, cell proliferation decreased to the remarkably-low proportion of 45% after treating cells with umbelliprenin-coated Fe3O4 MNPs. This suggests that with the aid of nanoparticles as carriers, natural products may have even broader range of medical applications in future

The combination effects of trivalent gold ions and gold nanoparticles with different antibiotics against resistant Pseudomonas aeruginosa

Despite much success in drug design and development, Pseudomonas aeruginosa is still considered as one of the most problematic bacteria due to its ability to develop mutational resistance against a variety of antibiotics. In search for new strategies to enhance antibacterial activity of antibiotics, in this work, the combination effect of gold materials including trivalent gold ions (Au ) and gold nanoparticles (Au NPs) with 14 different antibiotics was investigated against the clinical isolates of P. aeruginosa, Staphylococcus aureus and Escherichia coli. Disk diffusion assay was carried out, and test strains were treated with the sub-inhibitory contents of gold nanomaterial. Results showed that Au NPs did not increase the antibacterial effect of antibiotics at tested concentration (40 μg/disc). However, the susceptibility of resistant P. aeruginosa increased in the presence of Au and methicillin, erythromycin, vancomycin, penicillin G, clindamycin and nalidixic acid, up to 147 %. As an individual experiment, the same group of antibiotics was tested for their activity against clinical isolates of S. aureus, E. coli and a different resistant strain of P. aeruginosa in the presence of sub-inhibitory contents of Au , where Au increased the susceptibility of test strains to methicillin, erythromycin, vancomycin, penicillin G, clindamycin and nalidixic acid. Our finding suggested that using the combination of sub-inhibitory concentrations of Au and methicillin, erythromycin, nalidixic acid or vancomycin may be a promising new strategy for the treatment of highly resistant P. aeruginosa infections