Nanoemulsion containing dapsone for topical administration: a study of in vitro release and epidermal permeation

Abstract

Background: Topical administration of dapsone can be an alternative route for treatment of leprosy and can also provide new therapeutic applications for an established drug. However, the physicochemical properties of dapsone make it difficult to incorporate into conventional formulations. The current study was directed toward developing a stable nanoemulsion that contains dapsone which can be adapted for topical use. Methods: Nanoemulsions were prepared using isopropyl myristate or n-methyl-pyrrolidone as the oil phase, and characterized according to their mean droplet size, conductivity, refractive index, pH, drug content, and stability. The in vitro release of dapsone and its ability to permeate the epidermis were also evaluated. Results: Physicochemical characterization demonstrated that nanosystems were formed, which had a uniform droplet distribution and a pH compatible with the skin surface. Use of n-methyl-pyrrolidone provided a greater nanoemulsion region and higher solubilization of dapsone, and increased the in vitro release rate when compared with a nanoemulsion prepared using isopropyl myristate. However, use of isopropyl myristate promoted an increase in in vitro epidermal permeation that followed the Higuchi model. This demonstrates the ability of a nanosystem to influence permeation of dapsone through the skin barrier. Furthermore, the nanoemulsions developed and evaluated here had ideal physicochemical stability over a 3-month period. Conclusion: Incorporation of dapsone into a nanoemulsion may be a promising system for enabling topical delivery of dapsone, while minimizing skin permeation, for the treatment of acne. The method developed here used isopropyl myristate as the oil phase, and promoted permeation of dapsone through the skin barrier for the treatment of leprosy upon use of n-methylpyrrolidone as the oil phase.

Biocompatible Nutmeg Oil-Loaded Nanoemulsion as Phyto-Repellent

“…These results show that the pH values of NT 6 and NT 11 were stable throughout 90 days of storage at temperatures of 4 • C and 25 • C. The range of reported pH values was acceptable for topical administration (5.4-6.9) (Borges et al, 2013). In summary, droplet size and pH of both NT 6 and NT 11 were stable at storage temperatures of 4 • C and 25 • C but not at 60 • C. NT 6 and NT 11 are currently stored at the Herbarium Unit, Integrative Medicine Cluster, IPPT, USM with voucher numbers MF-004-NT6 and MF-004-NT11, respectively.…”

“…The pH values of NT 6 and NT 11 were 5.6 ± 0.16 and 5.3 ± 0.13, respectively. These pH values are suitable for topical administration to skin, as the pH of forearm skin is in the range of 4.2-5.9 (Borges et al, 2013). pH analysis is important to determine the stability and suitability of a product for topical application.…”

Design and optimization of nano invasomal gel of Glibenclamide and Atenolol combination: in vitro and in vivo evaluation

“…Regular samples were withdrawn at different time intervals up to 24 h and these were analyzed by HPLC. From the obtained data, flux is calculated by using the below formula [32,33]. The slope of the linear portion of the curve is calculated for a graph taken cumulative amount permeated per cm 2 on Y-axis and time on X-axis Steady state flux J ss ð Þ ¼ Slope of the linear portion of the curve= Surface area of diffusion cell…”

Influence of Terpene Type on the Release from an O/W Nanoemulsion: Experimental and Theoretical Studies

“…It described primarily the release of a drug from topical dosage forms, such as hydrogels, creams, and ointments. There were also reports to be found in the literature about lipophilic drug release from nanoformulations according to the Higuchi model [34][35][36][37]. To sum up, the best choice for a kinetic model is a drug-type dependent one.…”