Tailored nanocarriers for the pulmonary delivery of levofloxacin against Pseudomonas aeruginosa: a comparative study

Cystic fibrosis (CF) patients are faced with chronic bacterial infections displaying persistent resistance if not eradicated during the first stage of the disease. Nanoantibiotics for pulmonary administration, such as liposomal ciprofloxacin or amikacin, have progressed through clinics thanks to their sustained release, prolonged lung residence time and low systemic absorption. In this work, we sought a nanoformulation of levofloxacin for the treatment of Pseudomonas aeruginosa. We prepared and compared PLA-g-PEG nanoparticles, as well as anionic and cationic liposomes for their size, charge and encapsulation efficiency. Cationic liposomes were unable to encapsulate any drug and were subsequently considered as a control formulation. Regarding the efficiency of the nanocarrier, anionic liposomes exhibited a prolonged release over 72 h and preserved the antibacterial activity of levofloxacin against 5 strains of Pseudomonas aeruginosa, whereas polymeric nanoparticles quickly released their entire payload an...