Acetazolamide-Loaded Nanoparticle Based on Modified Hyaluronic Acid as Delivery System to Target Carbonic Anhydrases in Escherichia coli

Acetazolamide (AZA) is a validated carbonic anhydrase inhibitor (CAI) that has the potential for use in various therapeutic applications. Herein, we report a novel AZA-loaded biodegradable nanodelivery system that was proven to enhance the antibacterial efficacy of the drug against Gram-negative bacteria, such as <i>Escherichia coli.</i> Carbonic anhydrases (CA, EC 4.2.1.1) in <i>E. coli</i> play a crucial role in bacterial metabolism and CO₂/HCO₃^- balance; therefore, they represent a suitable target for antimicrobial strategies. The nanoparticles were obtained using a green synthetic protocol that allowed conjugation of a natural fatty acid to hyaluronic acid (HA) under solvent-free conditions. Full characterization of the micellar aggregates was performed (diameter of the micelles, zeta potential, and drug release study). In vitro studies demonstrated that AZA loaded in HA-based nanoparticles significantly inhibited <i>E. coli</i> growth at concentrations as low as 0.5 µg/mL, whereas higher concentrations of free AZA were required, as previously reported. Additionally, encapsulated AZA disrupted glucose consumption in <i>E. coli</i>, indicating its profound impact on bacterial metabolism. These findings suggest that the HA-palmitate nanoparticle not only enhances the delivery and efficacy of AZA but also offers a strategy to affect bacterial metabolism.