Enhanced oral bioavailability and sustained delivery of glimepiride via niosomal encapsulation: in-vitro characterization and in-vivo evaluation

Abstract

This study was designed to investigate the potency of niosomes, for glimepiride (GLM) encapsulation, aiming at enhancing its oral bioavailability and hypoglycemic efficacy. Niosomes containing nonionic surfactants (NIS) were prepared by thin film hydration technique and characterized. In-vitro release study was performed using a dialysis technique. In-vivo pharmacodynamic studies, as well as pharmacokinetic evaluation were performed on alloxan-induced diabetic rats. GLM niosomes exhibited high-entrapment efficiency percentages (E.E. %) up to 98.70% and a particle size diameter ranging from 186.8 ± 18.69 to 797.7 ± 12.45 nm, with negatively charged zeta potential (ZP). Different GLM niosomal formulation showed retarded in vitro release, compared to free drug. In-vivo studies revealed the superiority of GLM niosomes in lowering blood glucose level (BGL) and in maintaining a therapeutic level of GLM for a longer period of time, as compared to free drug and market product. There was no significant difference between mean plasma AUC_0-48 hr of GLM-loaded niosomes and that of market product. GLM-loaded niosomes exhibited seven-fold enhancement in relative bioavailability in comparison with free drug. These findings reinforce the potential use of niosomes for enhancing the oral bioavailability and prolonged delivery of GLM via oral administration.

Keywords:

• Glimepiride
• niosomes
• antidiabetic
• oral bioavailability
• sustained
• hypoglycemic

Acknowledgements

The authors would like to extend their appreciation to the Project’s Sector at the National Research Centre, Cairo, Egypt for funding this study through the research group project fund no P100202.

Disclosure statement

The authors report no declarations of interest.

Additional information

Funding

The authors would like to extend their appreciation to the Project’s Sector at the National Research Centre, Cairo, Egypt for funding this study through the research group project fund no P100202.