Preparation, Characterization and in vitro Release Studies of Enoxaparin in Nanoparticle form and Enterically Coated Tablets Containing Different Enhancers

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 derivatives have been studied as
permeation enhancer in free soluble form and as nanoparticulate systems. The aim of the current
work was to develop a nanoparticulate system based on ionic interaction between Trimethyl
Chitosan (TMC) and Enoxaparin as well as enterically coated Enoxaparin 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 using Acryl-Eze
, 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, 10 mg of surfactants as 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. The
Result suggests that the enhancing effect of the systems may be useful for oral Enoxaparin tablets.
In order to better evaluate the enhancing effect of the polymer with the surfactants as well as the
oral tablets with nanoparticulate systems further ex vivo and in vivo studies are required.