• Evaluation of antibacterial and antioxidant activity of betamethasone polymeric nanofibers against bacterial skin infections: in vitro analysis
  • Fatemeh Ashrafi,1,* Pooria Moulavi,2 Minoo Sadri,3
    1. Phd of Microbiology, Islamic azad university, North tehran branch, Tehran, Iran
    2. Department of Biology, Tehran North Branch, Islamic Azad University, Tehran, Iran
    3. Department of Biochemistry and Biophysics, Education and Research Center of Science and Biotechnology, Malek Ashtar University of Technology, Tehran, Iran.


  • Introduction: Skin and soft tissue infections (SSTIs) are among the most prevalent sorts of infections, with a wide range of etiologies and manifestations. Globally, the prevalence of SSTIs is larger than that of urinary tract infections and pneumonia combined, and it is constantly increasing. Skin infections have been associated with a multitude of organisms, which include Gram-positive and Gram-negative bacteria, fungi, and yeasts. It is therefore critical to assess alternative antimicrobial agents and therapeutic methods that target bacteria implicated in skin infection. Electrospinning is a flexible process for producing fibers with nanoscale micrometer diameters, significant oxygen permeability, variable pore diameters, and a substantial surface area ratio that is morphologically comparable to the extracellular matrix. As a result, electrospun nanofibers are suitable as wound dressing materials. Numerous chemicals have been electrospun into nanofibers to regulate their release. The purpose of the present survey was to analyze the feasibility of electrospinning commercially available betamethasone into nanofibers comprising of a mixture of honey, poly (ethylene oxide) (PEO), and Polyvinyl alcohol (PVA) to evaluate antimicrobial effects against skin infections.
  • Methods: At the first, for the synthesis of PEO / PVA / honey nanofibers containing betamethasone, all three polymer solutions of 12% PEO, 7% PVA, and 12% honey were prepared separately, and then a certain amount of drug was blended with polymers solution for the synthesis of polymer nanofibers containing 10% and 5% of betamethasone. The solution of the nanofibers containing10% of betamethasone was then placed in an electrospinning device under electrospinning conditions (25G, 0.1 cc/h Discharge Per Polymer, 15 cm, 10.5 kV). Finally, the obtained fibers were investigated by light microscopy (X40). The antibacterial effects of synthesized nanofibers were also investigated against skin infection bacteria including Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli, and Proteus mirabilis using well diffusion, disc diffusion, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) methods. The antioxidant capacity of IC50 concentrations of betamethasone-loaded polymeric nanofibers was assessed using an in vitro detection of intracellular reactive oxygen species generation in skin cancer cells
  • Results: The results of the current study showed that polymeric nanofibers containing different concentrations (5 and 10%) of betamethasone were well synthesized by the electrospinning method. Also, the antibacterial properties of synthesized nanofibers containing betamethasone were confirmed by MBC, MIC, well diffusion, and disc diffusion methods on the standard microbial strain involved in skin infections. The results of antibacterial tests also showed that nanofibers containing betamethasone had a 10% similar effect to gentamicin and this behavior was concentration-dependent. The results of antibacterial tests also showed that nanofibers containing betamethasone 10% had a similar effect to gentamicin and this behavior was concentration dependent; the strains treated with 5% betamethasone-polymeric nanofibers generated a smaller halo diameter than strains treated with gentamycin and 10% betamethasone-polymeric nanofibers. The most sensitive strain against synthesized nanofibers was the standard strain of Escherichia coli; however, the standard strain of Pseudomonas aeruginosa exhibited the highest resistance to these nanofibers. Antioxidant tests showed that the IC50 concentration of betamethasone-loaded polymeric nanofibers (283.22 μg/ml) had a greater ability to eliminate reactive oxygen species (ROS) than betamethasone alone (423.1 μg/ml) .
  • Conclusion: In conclusion, betamethasone was propitiously electrospun into honey/PEO/PVA nanofibers, and released betamethasone was capable to prevent the growth of standard strains of Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli, and Proteus mirabilis over a lengthened period of time. This formulation also is a proper antioxidant candidate against ROS in skin cancer treatment. Betamethasone-containing honey/PEO/PVA nanofibers may thus be appropriate wound dressing substances to decrease the bacterial burdens of infected skin wounds. Further investigation should focus on combining growth factors, anti-inflammatory drugs, and analgesics, as well as other possible antimicrobials agents to develop an ideal wound dressing that can treat infections and minimize the time required for wound healing.
  • Keywords: Antibacterial, Anti-oxidant, Electrospanning, Betamethasone, Skin bacterial infections