Piroxicam-loaded nanostructured lipid carriers gel: Design and characterization by square wave voltammetry

Abstract

Nanostructured lipid carriers (NLCs) based gel was developed as a potential topical system for piroxicam (PX) delivery. The characterizations of the semisolid formulation were assessed by using particle size distribution, polydispersity index, zeta potential analysis, and morphological and rheological studies. Square wave voltammetry (SWV) was selected as an alternative technique to study the release of PX from the carrier system. This technique allowed determinate the entrapment efficiency and the release profile of the NLCs. The study was carried out in in vitro condition using a Franz diffusion cell and an artificial cellulose nitrate membrane. The NLCs showed a 100 % encapsulation efficiency and a PX prolonged release, releasing the 60 % of the incorporated drug in 120 h. From the SWV study, it was also possible to understand the release kinetic mechanism of the proposed carrier system. Moreover, a histopathological examination was performed to evaluate the proposed topical formulation safety. This in vivo study was developed using male Wistar rats, and it confirmed the integrity of skin structure since no significant changes in rats epidermis, dermis, and hypodermis were found after 5 days of PX-loaded NLCs gel exposure. The results reveal a promising and stable alternative carrier system for PX topical delivery.