Moxifloxacin hydrochloride

The keto acid group at C3/C4 position of moxifloxacin chelates a non-catalytic Mg²⁺ ion, which then forms a hydrogen bonding network with the highly conserved Ser84 and Glu88 (Ser83 and Asp87 based on Escherichia coli GyrA numbering) on the subunit of topoisomerase IV A through four water molecules, constituting a "water-metal ion bridge".This bridge represents the primary interaction between clinically relevant quinolones and bacterial type II topoisomerases.

Fig. 1 Mechanism of action of Moxifloxacin. (Aldred, K. J.; et al. 2014)

Das Set al.developed a novel ophthalmic drug delivery system using PVA+chitosan composite film to load moxifloxacin hydrochloride for the treatment of conjunctivitis.The optimal formulation PC3 (PVA: chitosan = 7:3) performed best: it released 90% of the drug within 3 hours, exhibited strong antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa, caused no irritation to rabbit eyes, and demonstrated good biocompatibility. Compared to traditional eye drops, this film can achieve drug slow release, reduce the frequency of administration, and represents a safe and effective novel ocular drug delivery approach.

Fig. 2 Ocular irritation study of formulation PC3. (a) Right eye administered with normal saline at 0 h, (a1) Left eye administered with PC3 at 0 h, (b) Right eye administered with normal saline at 1 h, (b1) Left eye administered with normal saline at 1 h, (c) Right eye administered with normal saline at 24 h, (c1) Left eye administered with PC3 at 24 h, (d) Right eye administered with normal saline at 48 h, (d1) Left eye administered with PG3 at 48 h. (Das S, et al.2025 )