Linolenic acid conjugated chitosan micelles for improving the oral absorption of doxorubicin via fatty acid transporter

A novel delivery system based on linolenic acid (LA) conjugated chitosan (CS) polymeric micelles were proposed for improving the oral absorption of doxorubicin (DOX) through targeting intestinal fatty acid transporter. LA, as a ligand of the transporter, was grafted into CS to construct CS-LA micelles, and DOX was encapsulated into the micelles. The synthesized micelle material was identified by 1H NMR and FT-IR. The micelles showed regular spherical shapes with a particle size of 117.1 ± 1.6 nm, drug loading of 8.77 ± 0.02 %, and critical micelle concentration (CMC) of 23.6 μg/ml. The pharmacokinetics studies showed the relative bioavailability of 166 % versus DOX·HCl. The fatty acid transport protein 4-mediated intestinal uptake process of micelles was confirmed by the intracellular uptake, immunofluorescent imaging and permeation test. These findings confirmed the potential of CS-LA micelles as an effective oral delivery vehicle, and fatty acid transporter as a target spot for enhancing intestinal drug absorption.