Development of a sialic acid-containing hydrogel of poly[N-(2-hydroxypropyl) methacrylamide]: Characterization and implantation study

This study describes the preparation and the characterization of poly[N-(2-hydroxypropyl methacrylamide)] hydrogel with bulk-modified saccharidic portion of ganglioside GM(3) (Ncu5Ac-alpha 2,3-Gal-beta 1,4-Glc). The 3'-sialyllactose is a bioactive epitope recognized by many cell surface receptors on viruses, bacteria, and human cells such as growth factor receptors. Acrylated 3'-sialyllactose was synthesized and incorporated into the macromolecular network of hydrogels by free radical cross-linking copolymerization. Fluorescence techniques coupled to confocal laser scanning microscopy was employed to characterize the binding and accessibility of the sialyl group in the polymer network by using a monoclonal antibody against GM3 and the lectin wheat germ agglutinin. The morphology of the network was examined by scanning electron microscopy and confocal microscopy to image the gel morphology. The water content of sialyllactosyl-HPMA hydrogel compared to unmodified gel was characterized by swelling measurements and thermogravimetry. A preliminary implantation study in rat brain was performed to examine the biofunctionality of the sialyllactosyl hydrogel using an experimental model of Parkinson's disease.