Formulation and Physicochemical Characterization of Capecitabine-Loaded Cubosomes for Enhanced Drug Delivery System

Background: Capecitabine (CPB) is a hydrophilic anticancer drug classified as Biopharmaceutics Classification System (BCS) Class III, which presents challenges for effective dermal delivery. Objectives: This study aimed to develop and characterize a topical cubosomal formulation encapsulating CPB to enhance its delivery efficiency. Significance: By evaluating in vitro release and permeation behavior, this work investigates the potential of CPB-loaded cubosomes as an innovative targeted drug delivery system capable of achieving higher localized drug concentrations. Methods: CPB-loaded cubosomes were formulated using Pluronic F-68, Tween 80, and glyceryl monooleate. Four formulations were prepared by varying the concentrations of these excipients. A molten mixture of Pluronic F-68 and glyceryl monooleate was prepared, followed by incorporation of CPB under continuous stirring. The developed cubosomes were characterized for particle size, pH, zeta potential, viscosity, morphology (SEM), and in vitro drug release and permeation profiles. Results: The optimized formulation exhibited a particle size of 177.66 nm, and SEM confirmed well-segregated, nanosized cubic structures. Drug release from the formulations ranged from 40% to 67%, while permeation efficiency varied from 50% to 92%, demonstrating enhanced dermal transport of CPB. Conclusion: The CPB-loaded cubosomes demonstrated favorable physicochemical characteristics and significantly improved drug release and permeation, suggesting strong potential as an effective topical delivery system for capecitabine.