Overview   |   Catalytic Synthesis   |   Biomimetic Design   |   Functional Biomaterial
Functional Biomaterials for Biomedical Applications
Built upon efficient synthetic methods and biomimetic concepts, we further design new biomaterials for biomedical applications. To combine the advantages from both natural and synthetic systems, namely, the biocompatibility and biodegradability from natural components and the versatility from synthetic chemistry, we are exploring new strategies to design novel biomaterials from natural building blocks. In one project, we design new vectors for safe and effective delivery of small interference RNA (siRNA) to cells. For example, we designed a biodegradable peptide-based dendronized polymer (denpol) platform for siRNA delivery. The novel denpol architecture combines the multivalency of dendrimers and conformational flexibility of linear polymers for optimal siRNA binding and efficient delivery. Currently our lab is focused on designing a number of other new vectors as well as establishing structure-property relationships. In addition to siRNA delivery, the new vectors will also be investigated for the delivery of other genetic materials such as pDNA and mRNA for applications in gene therapy.
 
 
In another project, using the most abundant natural monomers such as saccharides and amino acids, we have developed a family of saccharide-peptide hybrid copolymers that are biodegradable, non-toxic, non-immunogenic, and highly functional. The combination of synthetic versatility, rich functionality, and inherent safe features makes this class of new biomaterials potentially useful for many biomedical applications. Currently, we are pursuing two directions of biomedical studies with our new biomaterials. In one study, we are developing stimuli-responsive nanogels as vectors for efficient delivery of small interference RNA (siRNA). In another investigation, we are designing saccharide-peptide based hydrogels as biomimetic extracellular matrices (ECMs) for stem cell and islet studies. Capitalizing the versatility and rich functionality of our biomaterials, we are programming chemical, physical, and biological information into our hydrogels to control cell fate. The ultimate goal for this project is to develop safe and functional synthetic scaffolds for tissue regeneration.
 
 
Representative publications:
1.
Multifunctional Dendronized Peptide Polymer Platform for Safe and Effective siRNA Delivery. Zeng, H.; Little, H. C.; Tiambeng, T. N.; Williams, G. A.; Guan, Z. J. Am. Chem. Soc., 2013, 135, 4962 – 4965.
2.
Maintaining Functional Islets through Encapsulation in an Injectable Saccharide-Peptide Hydrogel. Liao, S. W.; Rawson, J.; Omori, K.; Ishiyama, K.; Mozhdehi, D.; Oancea, A.; Ito, T.; Guan, Z.; Mullen, Y. Biomaterials , 2013, 34, 3984 – 3991.
3.
Modulation of Chondrocyte Behavior Through Tailoring Functional Synthetic Saccharide-Peptide Hydrogels” Chawla, K.; Yu, T.-B.; Stutts, L.; Yen, M.; Guan, Z. Biomaterials , 2012, 33, 6052 – 6060.
4.
De Novo Design of Saccharide–Peptide Hydrogels as Synthetic Scaffolds for Tailored Cell Responses. Liao, S.; Yu, T.-B.; Guan, Z. J. Am. Chem. Soc., 2009, 131, 17638-17646.
5.
Living Ring-Opening Polymerization of Carbohydrate-Derived Lactone for the Synthesis of Degradable Protein Resistant Biomaterials. Urakami, H.; and Guan, Z. Biomacromolecules, 2008, 9, 592-597.
6.
Saccharide-Peptide Hybrid Copolymers as New Biomaterials. Metzke, M.; Maiti, S.; O’Connor, N.; Guan, Z. Angew. Chem. Int. Ed. 2005, 44, 6529-6533.