(116al) Combinatorial Protein Encapsulation, Release, and Stabilization from Polyanhydride Films

We have developed high-throughput methods for measuring protein release and stabilization from polymer films in a combinatorial format. The biomaterials of interest were polyanhydrides composed of sebacic acid (SA), 1,6-bis(p-carboxyphenoxyhexane) (CPH), and 1,8-bis(p-carboxyphenoxy)-3,6-dioxaoctane (CPTEG), which have shown to be excellent drug-delivery devices due to their surface-erodible behavior and biocompatibility. For both CPTEG:CPH and CPH:SA compositions, a discrete polymer library encapsulating bovine serum albumin, BSA, was created with 5 replicates of 5 linearly varying polymer compositions by employing a rapid, automated deposition apparatus, and the surface chemistry verified using Fourier transform infrared (FTIR) spectroscopy. Protein release kinetics were measured using high-throughput techniques and demonstrated a slower release for the more hydrophobic compositions, correlating with previously published work. Discrete monomer/protein libraries were also created to study the antigenicity and structure of the protein at zero and seven days. No significant changes were detected for the CPTEG:CPH polymer library; however, there were slight changes detected with the CPH:SA library. These changes were correlated to the unfavorable, acidic environment provided by the polymer compositions containing high percentages of SA. The methods discussed in this work are amendable to many applications allowing for a more rapid and accurate design of materials used for drug and vaccine delivery.