Date of Award
Master of Science in Chemical Engineering
Chemical and Biomedical Engineering
Holland, Nolan B.
Biology, Biomedical Engineering
Star polymers are a class of branched polymers comprised of several polymer chains extending from a central point. Star polymers have applications in biopharmaceuticals where they have been proposed to be suitable drug delivery vehicles. Star polymers have traditionally been synthesized through chemical synthesis with added functionality provided by grafting on the arms. This complex synthesis can be simplified by using a biosynthetic approach which enables precise control of molecular weight and composition. This approach is demonstrated using star polymers with arms composed of a temperature responsive protein-based polymer termed elastin-like polypeptide (ELP). Star polymers are characterized based on the number of arms, the length of the arms, and the arm functionality. Previously, an ELP star polymer was synthesized with three arms. Here this work is extended through the synthesis of a six-armed ELP star polymer. The controlled synthesis of a complex six-armed star polymer has not been performed through biosynthesis techniques. The method of recursive DNA assembly used to prepare the gene that codes for the polypeptide has been designed to allow the preparation of genes encoding a range of arm lengths and variable functional end groups. A star polymer with six 19 pentapeptide long arms has been created with this system. This six-armed star polymer temperature dependent phase behavior is similar to the three-armed polymer containing 37 pentapeptides each.
Richard, Schmitt J. Jr., "A Synthesis Platform for Temperature Responsive Star Polymers" (2018). ETD Archive. 1068.