In Vitro Release Studies of Enoxaparin in Nanoparticle form and Enterically Coated Tablets Containing Surfactants

Document Type: Research Paper



In the past decade, many strategies have been developed to enhance oral drug delivery. Different techniques were investigated, amongst those the use of permeation enhancers such surfactants and biodegradable polymers were studied more extensively. Chitosan and its derivatives have been studied as permeation enhancer. The aim of the current study was to develop a nanoparticulate system based on ionic interaction between Trimethyl Chitosan (TMC) and Enoxaparin and comparing the release profile of enoxaparin from enterically coated tablets containing surfactants such as Tween 80 and Sodium Lauryl Sulfate (SLS) as permeation enhancer. The prepared nanoparticles were characterized for size, zeta potential, loading capacity and in vitro release. The tablets were enterically coated, characterized physically and were assayed for their content. The release of Enoxaparin was studied in PBS pH 6.8 corresponding to the pH of small intestine. The result suggested that the nanoparticles were positively charged with a diameter of about 120 nm and loading capacity of around 95%. The tablets contained 60 mg of Enoxaparin and 10 mg of surfactant as permeation enhancer. The in vitro release from tablets showed almost 100% Enoxaparin release in 2 hours; whereas in nanoparticles there was a 67.5% release in 24 hours. In order to better evaluate the enhancing effect of the polymer and surfactants in nanoparticle form and oral dosage tablet, further ex vivo and in vivo studies are required.