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oai:figshare.com:article/32640654 2026-10-01T16:29:21Z portal_1172 item_type_8 month_year_10_2026

Development of liposomal inhaled antibiotic formulations to target pulmonary infection Mona Al Hamod (24169419) PUREID: 625937592 Liposomes antibiotics inhalation lung infection Respiratory diseases such as cystic fibrosis, bronchiectasis, and chronic obstructive pulmonary disease (COPD) increase the susceptibility of the lungs to persistent bacterial infections, requiring repeated antimicrobial treatments often associated with systemic side effects. Inhaled liposomal antibiotic formulations offer a targeted alternative, enhancing drug concentration in the airways, minimizing systemic toxicity, and providing sustained drug release. <br><br>This thesis explores the development of inhalable liposomal formulations for two antibiotics, vancomycin and rifampicin. Vancomycin was encapsulated into liposomes using thin film hydration (TFH) and organic solvent-free (OSF) methods, achieving encapsulation efficiencies (EE) >50%. The dried vancomycin formulations demonstrated controlled in vitro release, stability at 20°C for 24 weeks, and comparable antimicrobial efficacy to free vancomycin against Staphylococcus aureus and MRSA, with enhanced activity against certain clinical isolates.<br><br>For rifampicin, TFH-loaded liposomes were spray-dried into powders with trehalose-based formulations yielding spherical particles suitable for inhalation, though requiring optimization. Nano spray-drying produced smaller, positively charged liposomes with improved powder properties. Liposomal rifampicin exhibited reduced minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) for Nontuberculous Mycobacteria (NTM), superior bactericidal activity, and enhanced targeting of intracellular bacteria in macrophages compared to free rifampicin. Both formulations showed no toxicity in lung cell lines up to 512 µg/ml. <br><br>This study demonstrates that inhalable liposomal formulations of vancomycin and rifampicin may hold a promise therapeutic options for treating bacterial lung infections in respiratory diseases, offering improved efficacy and safety profiles compared to conventional treatments. <br><br><i>Thesis is embargoed until 31 July 2027.</i><br> 2026-10-01T16:29:21Z Text Thesis 10.17034/32640654.v1 https://figshare.com/articles/thesis/Development_of_liposomal_inhaled_antibiotic_formulations_to_target_pulmonary_infection/32640654 All Rights Reserved Open Access after 2027-07-31