2026-09-21T06:00:41Z https://www.ideals.illinois.edu/oai-pmh

oai:www.ideals.illinois.edu:2142/24190 2023-07-10 col_2142_13836 col_2142_5131 com_2142_13835 com_2142_234 com_2142_5130

Cheng, Jianjun Cheng, Jianjun Braun, Paul V. Economy, James Moore, Jeffrey S. Lu, Hua 2011-05-25T15:02:59Z 2011-05-25T15:02:59Z 2011-05-25T15:02:59Z 2011-05 The goal of my Ph.D. research is to develop controlled/living polymerization techniques of α-amino acid N-carboxyanhydrides (NCAs) and synthetic polypeptides based materials. Polypeptides are a class of emerging biomaterials receiving increasing interests for various applications including drug delivery, gene therapy, antimicrobial and tissue engineering. The ring-opening polymerization (ROP) of NCAs has long been demonstrated as a powerful technique for preparation of high molecular weight (MW) synthetic polypeptides in gram scale. We developed a system utilizing organo-silicon amines, namely hexamethyldisilazane (HMDS) and N-trimethylsilyl (N-TMS) amines, for the controlled ROP of various NCAs. Predicable MWs and narrow molecular weight distributions (MWDs) of homo- and block- polypeptides can be prepared via this methodology. Our mechanism study illustrated that the polymerization involves formation of trimethylsilyl carbamate (TMS-CBM) structure at the propagation center. In addition, the system allows facile end group and side-chain functionalization of the polypeptides and integration of NCA ROP with other polymerization techniques such as ring-opening metathesis polymerization (ROMP) to prepare hybrid polypeptides materials. Finally, we discovered a new type of ionic polypeptides with unusual helical stability and demonstrated that they have great potential for gene delivery and siRNA delivery applications. Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2011-03-08T18:18:33Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Lu_Hua.pdf: 3904762 bytes, checksum: dd1e6e362be261874d62a40a46b89338 (MD5) Made available in DSpace on 2011-05-25T15:02:59Z (GMT). No. of bitstreams: 3 Lu_Hua.pdf: 3904747 bytes, checksum: def709a6a74aabf4d9331bc1332c942b (MD5) license.txt: 4054 bytes, checksum: 193dcc14a6204921e03161d1efe96454 (MD5) 1_license.txt: 4054 bytes, checksum: d4a409e08fa2cdc67d82dde8675336d3 (MD5) http://hdl.handle.net/2142/24190 en Copyright 2011 Hua Lu N-carboxyanhydrides (nca) Polypeptides Controlled-polymerization Helix gene-delivery Amino acid N-carboxyanhydrides and polypeptides: Controlled polymerization, properties and applications Materials Science & Engineerng 1919 Materials Science & Engr 0130 University of Illinois at Urbana-Champaign Dissertation Ph.D. PHD:Materials Sci & Engr -UIUC 10KS0130PHD