Berkeley Lectures in Chemical and Biomolecular Engineering presented by The Dow Chemical Company: Functionalizable Polypeptides and Polymeric siRNA Smart Delivery

Lecture: Chem. & Biomol. Engineering Colloquium: Special Seminar | September 18 | 4-6 p.m. |  Anthony Hall

 Paula T. Hammond, Professor, Massachusetts Institute of Technology

 Department of Chemical Engineering

The controlled polymerization of N-carboxyanhydride monomers provides a means of generating synthetic polypeptides; however, until recently, only native amino acids were incorporated along the backbone. Our lab introduced an alkyne functionalized monomer, propargyl-L-glutamate, that enables the use of click chemistry post-polymerization, thus allowing the generation of a broad range of different functional side groups. Poly(propargyl-L-glutamate) (PPLG), and similar polypeptides subsequently introduced, has enabled a broad range of new approaches to designing artificial polypeptide systems with properties that engage or mimic biology. On the other hand, interesting new biological macromolecules can be engineered from nucleic acids. Newer synthetic methods in our laboratory include the use of rolling circle transcription to create periodic-shRNA (pshRNA) consisting of hundreds of repeat units that spontaneously assemble into RNAi microsponges. We have found that these polymeric forms of siRNA can yield activation of immunological pathways that facilitate further tumor cell death, while also inducing knockdown of targeted genes. Applications of these systems toward active or responsive drug delivery applications will be discussed.