Implementing Central Composite Design for Developing Transdermal Diacerein-Loaded Niosomes: Ex vivo Permeation and In vivo Deposition

BACKGROUND: Niosomes are surfactant-based vesicular nanosystems that proved their efficien-cy in transdermal delivery by overcoming skin inherent anatomic barrier; startum corneum. Central com-posite design is an efficient tool for developing and optimizing niosomal formulations using fewer exper-iments. OBJECTIVE: The objective of this study was to prepare niosomes as a transdermal delivery system of di-acerein using film hydration technique, employing central composite design, for avoiding its oral gastroin-testinal problems. METHODS: Three-level three-factor central composite design was employed for attaining optimal niosomes formulation with the desired characteristics. Three formulation variables were assessed: amount of salt in hydration medium (X1), lipid amount (X2) and number of surfactant parts (X3). DCN-loaded niosomes were evaluated for entrapment efficiency percent (Y1), particle size (Y2), polydispersity index (Y3) and zeta potential (Y4). The suggested optimal niosomes were subjected to further characterization and utilized as a nucleus for developing elastic vesicles for comparative ex vivo and in vivo studies. RESULTS: The values of the independent variables (X1, X2 and X3) in the optimal niosomes formulation were 0 g, 150 mg and 5 parts, respectively. It showed entrapment efficiency percentage of 95.63%, parti-cle size of 436.65 nm, polydispersity index of 0.47 and zeta potential of -38.80 mV. Results of ex vivo permeation and skin deposition studies showed enhanced skin permeation and retention capacity of the prepared vesicles than drug suspension. CONCLUSION: Results revealed that a transdermal niosomal system was successfully prepared and evaluat-ed using central composite design which will result in delivering diacerein efficiently, avoiding its oral problems.