Chitosan nanoparticles for the intracellular delivery of triphosphate nucleotide analogues

Aim Nucleotide analogues such as Azidothymidine-triphosphate (AZT-TP), the active form of Zidovudine, display an important pharmacological activity for the treatment of HIV. The administration of these nucleotide analogues would bypass the intracellular phosphorylation which can be a metabolic bottleneck. This possibility is however limited by their instability in physiological conditions, and furthermore their hydrophilicity restricts their access to the target cells. Several nanocarriers have been proposed so far for the encapsulation of these molecules, but their applications are limited due to the low drug loading achieved. Our strategy proposes the use of chitosan, a biocompatible and hydrophilic polysaccharide which is known to form nanoparticles through complexation with TPP; in contrast with previous methods, in our case the drug itself will be the driving force for the formation of nanoparticles [1].