Poly(ethylene glycol) hydrogel microspheres as a controlled release device

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2005.Includes bibliographical references (leaves 28-32).Vaccines for infections such as measles, polio, or chicken pox contain live attenuated viruses, which can sometimes lead to infection. Our objective is to develop an improved strategy for vaccines that induces patent immune responses against persistent viral infections. Three processes must occur to successfully produce immunity; the first is the attraction of immature Dendritic Cells (DCs), loading them with particular antigens, and then maturing the DCs. This project focuses on DC attraction to an immunization site by fabricating crosslinked polyethylene glycol hydrogel microspheres that encapsulate a chemoattractant. This study was performed to determine whether the diffusion of the chemoattractant could be controlled by varying the amount of crosslinker and by incorporating ionic groups in the polymer matrix. It was found that the crosslinker amounts successfully altered the release profiles of the protein. The ionic groups incorporated in the polymer matrix effectively altered the diffusion of both positively and negatively charged protein diffusion.by Sandra D. González.S.B