Acyclovir-Loaded Chitosan Nanospheres from Nano-Emulsion Templating for the Topical Treatment of Herpesviruses Infections

Abstract

Acyclovir is not a good candidate for passive permeation since its polarity and solubility limit is partitioning into the stratum corneum. This work aims to develop a new topical formulation for the acyclovir delivery. New chitosan nanospheres (NS) were prepared by a modified nano-emulsion template method. Chitosan NS were characterized by Dynamic Light Scattering (DLS), Transmission Electron Microscopy (TEM), and an in vitro release study. The in vitro skin permeation experiment was carried out using Franz cells and was equipped with porcine skin. Biological studies were performed on the Vero cell line infected by HSV-1 and HSV-2 strains. The acyclovir loaded chitosan NS appeared with a spherical shape, a size of about 200 nm, and a negative zeta potential of about 40.0 mV. The loading capacity of the drug was about 8.5%. In vitro release demonstrated that the percentage of acyclovir delivered from the nanospheres was approximately 30% after six hours. The in vitro skin permeation studies confirmed an improved amount of permeated acyclovir. The acyclovir-NS complex displayed a higher antiviral activity than that of free acyclovir against both the HSV-1 and the HSV-2 strain. The acyclovir-loaded NS showed no anti-proliferative activity and no signs of cytotoxicity induced by NS was detected. Confocal laser scanning microscopy confirmed that the NS are taken up by the cells.

The Role of Pharmaceutical Nanotechnology in the Time of COVID-19 Pandemic

“…NE with particles size around 200 nm showed higher ability to overcome the porcine skin barrier than free drug, assessed by in vitro permeation test. The enhanced anti-herpes zoster activity was noticed, with higher HSV-1 and HSV-2 infected cells uptake than control, confirmed by confocal laser scanning microscopy [ 75 ]. On the other hand, the hepatitis C virus (HCV) is an important RNA virus that affects the human's life quality.…”

Nanotechnology-based antiviral therapeutics

“…Chitosan nanospheres loaded with acyclovir were synthesized using modified nanoemulsion template method for topical treatment of herpes. The spheres were of the average size of 200 nm and showed better permeation in in vitro skin permeation studies and higher potency against HSV-1 and HSV-2 than the free acyclovir itself [145].…”

Nanomaterials Designed for Antiviral Drug Delivery Transport across Biological Barriers

“…Donalisio et al [155] have reported the preparation by a modified nano-emulsion method of chitosan nanospheres (NS) loaded with 8.5% ACV as a topical formulation against both HSV-1 and HSV-2 herpes virus strains. The main component, chitosan, a natural polycationic polysaccharide, was selected as a material for ACV release, due to its distinctive properties: hydrophilic character, in situ gelling, mucoadhesion, permeation enhancing, in addition to a low cytotoxicity, biocompatibility and bioresorbability features [165].…”