DEVELOPMENT, CHARACTERIZATION, AND OPTIMIZATION OF REPAGLINIDE LOADED SPANLASTICS ALONG WITH INVESTIGATION OF DRUG SOLUBILITY IN VARIOUS MEDIA

Hesham Seary; Elsaied H. Barakat; Mohamed A. Raslan; Ahmed M. Samy

doi:10.22270/ujpr.v9i5.1221

Hesham Seary Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Al Azhar University, Cairo Egypt.
Elsaied H. Barakat Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Al Azhar University, Cairo Egypt.
Mohamed A. Raslan Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Al Azhar University, Cairo Egypt.
Ahmed M. Samy Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmacy, Al Azhar University, Cairo Egypt.

10.22270/ujpr.v9i5.1221

Keywords:

Optimization, physicochemical characterization, repaglinide, solubility enhancement, spanlastics, thin-film hydration technique

Abstract

Objective: This study seeks to explore the solubility of an antidiabetic drug with poor water solubility, Repaglinide (RPG), in various media, and develop and optimize RPG-loaded spanlastic formulations.

Methods: A 72-hours solubility study was conducted for RPG in different media, followed by UV spectrum analysis. Spanlastics containing RPG were prepared through the thin-film hydration (TFH) method combined with ultrasonication, incorporating varying concentrations ofthe lipophilic, non-ionic surfactant agents, Span 60 and Tween 80. Characterization was performed To assess particle size (PS), polydispersity index (PDI), zeta potential (ZP), and entrapment efficiency (EE%). Optimization was achieved by analysing characterization results and using a mixture design of Design Expert software which predicted the optimized formula.

Results: RPG exhibited the highest solubility in phosphate buffer saline (PBS, pH 6.8) incorporating 0.5% Tween 20 (168.595 µg/mL), followed by PBS with 0.1% Tween 80 (80.355 µg/mL), PBS alone (56.163 µg/mL), and PBS with 0.1% sodium lauryl sulphate (SLS) (53.706 µg/mL). UV scanning in methanol revealed three characteristic absorption bands for RPG, with peak selection optimized for molar absorptivity in each medium. The RPG-loaded spanlastic formulations demonstrated nano-sized vesicles with uniform size distribution, high stability, and efficient drug encapsulation. Optimized spanlastics predicted a particle size 126.162 nm, PDI 0.416, ZP-43.258 mV, and EE% 77.753%.

Conclusions: This research emphasizes the potential of optimized RPG-loaded spanlastics, developed through the thin-film hydration method, as a promising approach for improving the solubility and stability of poorly water-soluble drugs. RPG showed the highest solubility in PBS (pH 6.8) containing 0.5% Tween 20, and the formulation achieved desirable nanosize, uniformity, and high encapsulation efficiency.