Microwave-assisted graft copolymerization of amino acid based monomers onto starch and their use as drug carriers

• Amino acid-based monomers were synthesized and grafted onto starch by microwave.
• The graft copolymer was applied as drug (atenolol) carrier for colon targeting.
• The drug showed 95.3% release in alkaline medium and only 27.8% in acid medium.

This paper describes the synthesis of two amino acid-based monomer and their graft copolymerization onto starch and utilization of the prepared graft copolymers as drug carriers. The two monomers were synthesized and reacted with acryloyl chloride to get the corresponding acryloylamino acid, which were further grafted onto starch using the microwave-assisted grafting technique. All factors affecting the efficiency of the grafting reaction were studied and the prepared graft copolymers were fully characterized. Atenolol, as a model drug in the form of salt was immobilized onto the graft copolymers by ionic bonds and the loading was confirmed by use of FT-IR, TGA and NMR. The drug release was studied in both acidic and alkaline media and it was found that the release takes place in alkaline medium rather than in acidic medium and this indicates that these polymers can be used as carriers for drugs whose target is the colon.