Effect on Nail Structure and Transungual Permeability of the Ethanol and Poloxamer Ratio from Cyclodextrin-Soluble Polypseudorotaxanes Based Nail Lacquer.

Elena Cutrín-Gómez,José Gómez-Amoza,M Delgado-Charro,Soledad Anguiano-Igea,Francisco Otero-Espinar

doi:10.3390/pharmaceutics10030156

Elena Cutrín-Gómez, José Gómez-Amoza + Show 3 more

Open Access

https://doi.org/10.3390/pharmaceutics10030156

Copy DOI

Abstract

Aqueous-based nail lacquers have shown potential in promoting the diffusion of drugs into the nail. In our laboratory, we have recently developed a transungual delivery system based on an aqueous dispersion of cyclodextrin-poloxamer soluble polypseudorotaxanes, supramolecular host−guest assemblies that improves the drug permeation into the nail. However, the high-water content and the rheological and adhesive properties of this lacquer negatively affect properties that play a fundamental role in the patients’ acceptance such as stickiness, nail film formation or drying rate, properties. In this work, we have optimized the composition of these lacquers to improve these properties whilst maintaining good drug permeation profiles. Incorporating ethanol into the vehicle and reducing the proportion of Poloxamer 407 (PL), provided a good strategy. The use of hydro-ethanolic mixtures (>50% ethanol) and the reduction of the poloxamer concentration significantly improved the lacquer drying speed by reducing the stickiness and promoting film formation on the nail surface. Additionally, in a surprising way, the use of hydro-ethanolic vehicles further enhanced the permeation of ciclopirox olamine and clobetasol propionate, used for the treatment of onychomycosis and nail psoriasis respectively, into the nail and hooves.

Highlights

Research into new formulations to topically treat the ungual areas has grown in importance because nail diseases are becoming more frequent
The permeability of the nail plate depends on several factors, nail hydration and swelling [6,7,8]
This was confirmed by Walters et al [9] who discovered that a hydrated nail is more permeable to water than to alcohol and deduced that the nail plate behaves like a hydrogel

Summary

Introduction

Research into new formulations to topically treat the ungual areas has grown in importance because nail diseases are becoming more frequent. Available treatments for these pathologies include oral antifungals, which are considered efficacious but have adverse effects and may cause drug interactions [1]. The permeability of the nail plate depends on several factors, nail hydration and swelling [6,7,8]. The same work demonstrated that diluted alcohols possessed a much higher nail permeability coefficient than some other alcohols, further confirming the role of water in facilitating ungual permeation. Nail hydration can be considered a simple tool with which to improve the penetration of drugs through the nails [13]

Objectives

Methods

Results