Karrar Sachit Salim (1), Ahmed Najim Abood (2), Ayad Almakki (3)
Skin and soft tissue infections (SSTIs) caused by Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae represent a growing clinical challenge due to increasing antimicrobial resistance and limitations of conventional topical therapies. Levofloxacin is an effective broad-spectrum fluoroquinolone; however, its topical efficacy is restricted by inadequate skin penetration and rapid drug loss at the application site. Nanovesicular carriers such as bilosomes have been proposed to enhance dermal drug delivery through improved stability and skin permeation. Limited studies have evaluated the physicochemical suitability and in-vitro antibacterial performance of levofloxacin-loaded bilosomal gels compared with conventional levofloxacin preparations. This study aimed to develop a levofloxacin bilosomal gel and evaluate its physicochemical properties and in-vitro antibacterial efficacy against common SSTI pathogens. Levofloxacin bilosomal gels exhibited skin-compatible pH (6.2–6.8), good spreadability, pseudoplastic rheological behavior, and uniform drug content (96.7–99.2%). In agar well-diffusion assays, bilosomal formulations (F1 and F2) produced significantly larger zones of inhibition than standard levofloxacin against E. coli, S. aureus, and K. pneumoniae at concentrations ≥32 µg/mL (p < 0.05), while no differences were observed at 0.5 µg/mL. Formulation F2 consistently demonstrated the highest antibacterial activity across all tested organisms. This study demonstrates enhanced antibacterial efficacy of levofloxacin through bilosomal encapsulation within a topical gel system. Levofloxacin bilosomal gel represents a promising topical delivery approach for improving local antibacterial efficacy in the management of skin and soft tissue infections.
Highlights
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