Hydrogen sulfide-sensitive Chitosan-SS-Levofloxacin micelles with a high drug content: Facile synthesis and targeted Salmonella infection therapy.

The delivery system of antibiotics plays an important role in increasing the drug efficacy and reducing the risks of off-target toxicities and antibiotic resistance. The pathophysiology of bacterial infections is similar to that of tumor tissues, but only a few delivery systems have been able to target and release antibiotics on demand. Herein, we designed and developed a robust Chitosan-SS-Levofloxacin (CS-SS-LF) micelles for targeted antibiotic delivery, in which disulfide bond can be reduced by hydrogen sulfide (H2S), a typical product of Salmonella, and subsequently released antibiotic to eradicate Salmonella infection. CS-SS-LF micelles showed uniform size and sharp response to H2S. Compared with levofloxacin alone, these micelles possessed a better capacity in disrupting Salmonella biofilms and reducing bacterial burden in organs. The H2S-sensitive CS-SS-LF micelles might enable a new way to address bacterial infections.