Novel Carriers for Oral Delivery of Hydrophobic Drugs

Abstract

For the first time, the glucose-6-acrylate-1,2,3,4-tetraacetate (GATA) monomer was prepared under mild conditions. The removal of protecting acetate groups from GATA was carried out before the silylation and then Me₃Si was covalently linked with glucose acrylate (GA). Cubane-1,4-dicarboxylic acid (CDA) was covalently linked with 2-hydroxyethyl methacrylate (HEMA). The silyl-linked GA is abbreviated as TMSiGA. CDA linked to two HEMA groups was used as the cross-linking agent (CA). Free radical cross-linking co-polymerization of the methacrylic acid (MAA) and hydrophobic glycomonomer (TMSiGA) with two different molar ratios of CA was carried out at 60–70°C. The compositions of the cross-linked three-dimensional polymers were determined by FT-IR spectroscopy. A model hydrophobic drug, the steroid hormone estradiol, was entrapped in these gels and the in vitro release profiles were carried out in enzyme-free simulated gastric and intestinal fluids (SGF and SIF, respectively). To overcome the hydrophobicity of estradiol, the buffers for estradiol were modified by adding ethanol. The influence of the structures and amounts of silane monomers on the swelling and drug-release behaviors were studied.

Keywords:

• HYDROPHOBIC DRUG
• PH SENSITIVITY
• HYDROGEL
• ORAL DRUG DELIVERY
• ESTRADIOL