Fabrication and evaluation of a sulfacetamide-loaded niosomal gel for the treatment of ocular bacterial infections

Topical ocular drug delivery is often restricted by rapid precorneal clearance, which can decrease drug residence time and bioavailability at the ocular surface. The purpose of the study was to develop a sulfacetamide-loaded niosomal gel (SA-Nio-Gel) to enhance ocular drug delivery. Thin film hydration method was used for the preparation of SA niosomes, employing nonionic surfactants (Span 60 and Span 80) and cholesterol. The optimized niosomal formulation was then incorporated into a Carbopol 934 gel base to prepare the final SA-Nio-Gel formulation. The optimized niosomes exhibited encapsulation efficiency of 76% ± 1.5 and a mean particle size of 129.7 ± 2.52 nm. Rheological analysis of the SA-Nio-Gel demonstrated pseudoplastic behavior, characterized by a reduction in viscosity with increasing shear rate. Biocompatibility evaluation indicated that the formulation was non-toxic. In vitro release profiles showed a slow and sustained SA release from the developed formulation. Furthermore, microbiological assays confirmed the potent antibacterial activity of the SA-Nio-Gel against S. aureus. Compared to the SA solution and SA-Nio, the SA-Nio-Gel formulation significantly minimized precorneal drainage and improved drug penetration. These results indicate that the niosomal gel-based system could be a promising platform for the ocular delivery of SA, which provides sustained release and enhanced drug permeability.