(327d) Enhanced Mucoadhesive Capacity of Novel Copolymers for Oral Protein Delivery

Graft copolymer networks of poly (methacrylic acid) (PMAA) containing well characterized tethers of poly (ethylene glycol) (PEG) have proven to be adequate devices for oral delivery of proteins. Yet, further improvements are needed to be viable. One approach is to increase adhesion at the delivery site, which we have done by utilizing small chemical linkages caused by the addition of an aldehyde functional group to the PEG tethers. These aldehydes bind with the amines of the amino acids found in the glycoprotein network of the mucus layer of the small intestine. To investigate the effectiveness of this linkage the copolymers are prepared in different ratios of PEG and aldehyde modified PEG and characterized through swelling and adhesion testing. The swelling results indicate no deviation from the already present pH sensitivity with the inclusion of the aldehyde modified PEG. Adhesion testing was carried out through the use of a mechanical testing apparatus. Data was gathered and plotted to give a detachment force (N) versus displacement (m) curve, of which the work of adhesion (µJ) was found by taking the area underneath the curve. Adhesion results indicate an increase to the already present adhesion of the copolymers due to increased percentages of the aldehyde modified PEG tethers.