Porous starch based self-assembled nano-delivery system improves the oral absorption of lipophilic drug.

The therapeutic efficacy of lipophilic drugs is commonly restricted by the low systemic exposure after oral administration. In this work, a new delivery system combining the advantages of porous starch and self-assembled nanocarrier was designed to improve the oral absorption of lipophilic drugs. The lipophilic probucol loaded porous starch based self-assembled nano-delivery (PSN) system was developed and characterized. The probucol loaded nanocarrier (PLN) could be formed by self-assembly when PSN was dispersed into the gastrointestinal (GI) fluids. PLN was nanometer-sized particles with narrow size distribution and exhibited good stability in GI fluids. The aqueous solubility of probucol was increased over 50,000-fold by PSN delivery system and the cumulative release of lipophilic probucol was increased over 80% in GI fluids. The distribution of probucol in duodenum, jejunum and ileum was respectively improved 7.17, 15.99 and 33.61-fold by PSN. In particular, the oral bioavailability of probucol from PSN was greatly improved about 9.96-fold than that from free drug suspension and 3.71-fold higher than that from the directed adsorbed probucol loaded porous starch system, which effectively confirmed the high potential of the strategy in enhancing the oral absorption of lipophilic drugs.