Enhanced Antibiofilm Efficacy of Ciprofloxacin-Loaded Quatsomal Gel Formulation Against Multidrug-Resistant Superbug Methicillin-Resistant Staphylococcus Aureus

Background: MRSA biofilms pose a significant challenge in clinical settings due to their resistance to antibiotics and persistence in infections. This current study formulated and evaluated the ciprofloxacin-loaded quatsomes in gel formulation to enhance topical antimicrobial and antibiofilm efficacy against MRSA. Formulation was prepared using a probe sonication method with CTAB and cholesterol, followed by incorporation of ciprofloxacin. Results: The resulting formulation was characterized by particle size, zeta potential, TEM, encapsulation efficiency, and FTIR spectroscopy. A HPMC-based gel was developed for topical delivery and antimicrobial and antibiofilm activities were assessed. An in vivo wound excision model in mice evaluated the therapeutic efficacy of this formulation. The loaded formulation exhibited a mean particle size of 154.6±0.7 nm, PDI of +51.3±1.3mV and 79±0.4% ciprofloxacin encapsulation efficiency. FTIR confirmed the drug incorporation along with pH, spreadability, and viscosity testing within specific ranges for skin application. Optimized formulation significantly reduced MRSA growth with a minimum inhibitory concentration of 64 µg/mL and 91.32±0.14% biofilm inhibition. In vivo studies revealed 98% wound contraction and ~ -4 log ¹⁰ CFU reduction with the loaded quatsomes group compared to 82% with the ciprofloxacin group. Conclusion: Formulation showed potent antimicrobial and antibiofilm activity against MRSA and represents a promising alternative for treating biofilm-associated skin infections.