This research was designed to develop thermoresponsive poloxamer (P407)–polyvinyl alcohol (PVA) hydrogels to deliver mupirocin nanoparticles for wound healing. The mupirocin nanoparticles containing drug and gelatin or poly (acrylic acid) were prepared by spray drying. The hydrogel phases were evaluated by small‐angle X‐ray scattering. An in vitro drug release study was performed and the antibacterial activity of mupirocin nanoparticles‐loaded hydrogel (MLH) was evaluated. Fourier transform infrared and proton nuclear magnetic resonance spectrum spectra of the mupirocin nanoparticles indicated a weak interaction between mupirocin and the carriers of carbopol and gelatin. The mupirocin molecules were surrounded by the carrier molecules. The MLH appeared to exhibit single diamond (Fd3m) phase behavior similar to P407 and the hydrogel base. The release of MLH in vitro indicated first‐order kinetics (R2 = .9839–.8868). The MLH showed lower minimum inhibitory concentrations and minimum bactericidal concentrations against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli than mupirocin ointment.

No abstract

This novel study investigated the loading of mupirocin nanoparticles into a hydrogel which was expected to enhance the antibacterial activity of mupirocin. The inhibition of isoleucyl-tRNA synthetase and global gene expression in methicillin-resistant Staphylococcus aureus (MRSA) by the mupirocin nanoparticle-loaded hydrogel (MLH) and by pure mupirocin was compared. MLH and mupirocin rapidly inhibited the growth of bacterial populations after 1 h of treatment. At 12 h, mupirocin and MLH inhibited isoleucyl-tRNA synthetase in MRSA. Transcriptome profiles of MRSA showed that gene expression alterations after treatment with mupirocin were similar to those after treatment with MLH at MICs. These alterations included changes to DNA transcription, translation, and replication pathways, and the fold changes in these genes decreased more rapidly with MLH than with mupirocin only after 1 h of treatment. MLH released the mupirocin from the nanoparticles and hydrogel systems and then the drug permeated the cell wall and bound to bacterial isoleucyl-tRNA synthetase. The research also showed that MLH could be further developed for use in clinics for infected wounds.

No abstract