Preparation and characterization of a novel thermosensitive and bioadhesive cephalexin nanohydrogel: a promising platform for topical antibacterial delivery

ABSTRACT

Objective

Impetigo is a common and highly contagious bacterial skin infection that mostly affects young children and infants. Herein, we report the development of a thermosensitive and bioadhesive in-situ hydrogel-forming system containing cephalexin-loaded nanoparticles (NPs) suitable for antibacterial drug delivery.

Methods

The nanohydrogel was formulated using drug-loaded NPs and characterized by its physicochemical characteristics. Antibacterial activities of the cephalexin NPs and nanohydrogel were examined in vitro against Staphylococcus aureus (S. aureus). The ex vivo drug permeation study was performed using rat skin. Finally, this formulation was tested for in vivo antibacterial activity using superficial skin infections in rats.

Results

The mean size and entrapment efficiency of the NPs were found to be 178 nm and 58%, respectively. The transmission electron microscopy analysis verified the formation of spherical NPs. The drug-loaded NPs showed an enhanced eradication effect against S. aureus according to the declined MIC values in comparison with the untreated drug. The ex vivo permeation profile of the cephalexin nanohydrogel showed a slow release pattern for 8 h. When applied on rat skin for 6 days, the nanohydrogel exhibited a superior antibacterial activity with normal hair growth and skin appearance as compared to the plain drug hydrogel.

Conclusions

These findings suggested that the nanohydrogel could serve as a valuable drug delivery platform against superficial bacterial infections.

KEYWORDS:

• Cephalexin
• impetigo
• nanoparticles
• polycaprolactone
• skin infection
• Staphylococcus aureus

Acknowledgments

The authors would like to acknowledge the support of the Elite Researcher Grant Committee from the National Institute for Medical Research Development (NIMAD) (Grant No. 977515) for funding this project. We are also thankful for the technical support provided by the Faculty of Pharmacy at Tabriz University of Medical Sciences.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This work was supported by the National Institute for Medical Research Development (NIMAD) [Grant number 977515] and approved by its ethics committee (Code: IR.NIMAD.REC.1397.433), Tehran, Iran.