Development and Evaluation of Acetazolamide-Loaded Nanospanlastic Gel for Enhanced Ocular Delivery

Abstract

Background: Acetazolamide, a potent antiglaucoma agent, lacks effective topical ocular delivery due to low aqueous solubility, corneal permeability, and short elimination from the precorneal area, hence low bioavailability and frequent dosing.

Aim: The current study aims to establish an acetazolamide-loaded nanospanlastic ocular gel to improve corneal permeability, increase ocular residence time, and provide sustained release for the therapy of glaucoma.

Methodology: Nanospanlastic vesicles were formed using the ethanol injection method. The drug purity, compatibility, and preformulation studies were carried out. The optimized nanospanlastics were characterized, and the final product in the form of a mucoadhesive gel was prepared. The physicochemical studies were done, followed by in vitro drug release, ex vivo corneal permeation, and stability studies.

Results: The optimized formulation had a particle size of 154.8 ± 2.11 nm, zeta potential of −28.6 ± 0.92 mV, and entrapment efficiency of 79.65 ± 1.14%. Ocular gel showed physiological pH, adequate viscosity, reproducible drug content, controlled drug release for a period of up to 12 h, and improved corneal permeation. The stability studies confirmed the integrity of the formulation during three months.

Conclusion: The developed acetazolamide-loaded nanospanlastic gel is a stable and effective ocular delivery system that may provide improved management of glaucoma.

Keywords: Acetazolamide; Corneal permeation; Glaucoma therapy; Nanospanlastics; Ocular drug delivery; Sustained drug release