内容简介：

We are designing and synthesizing smart polymers for uses in microfluidic diagnostic devices for diagnosing the presence of specific disease markers in a small blood sample. We conjugate the polymer chains to proteins, or coat polymeric and magnetic nanoparticles with them. The smart polymers are usually synthesized using RAFT living free radical polymerization techniques. This allows us to control molecular weight and to achieve a narrow MW distribution of the polymers.  Furthermore, RAFT polymers have reactive end groups that we are using to conjugate the polymers to the proteins and to coat the nanoparticles. The smart polymers we work with include temperature-responsive polymers such as poly(N-isopropyl acrylamide) or PNIPAAm and pH-responsive polymers such as poly(propylacrylic acid) or PPAA. We are synthesizing random, block and graft copolymers of these compositions as well. We then conjugate the smart polymers to capture proteins such as streptavidin or monoclonal antibodies. We have also UV-grafted the smart polymers to the silicone rubber channel surfaces in the microfluidic devices. In addition, we have coated the smart polymers onto polystyrene nanoparticles and magnetic iron oxide nanoparticles by a variety of techniques. The microfluidic devices will have various regions that are heated or cooled, and also other regions where we can modify pH or stimulate with UV light. The stimuli-induced phase separations will be used to isolate the captured markers on the channel walls, for later collection and assay.

Selected References

• A.S. Hoffman, et al., “Really Smart Bioconjugates of Smart Polymers and Receptor   Proteins”, J. Biomed. Mater. Res., 52, 577-586 (2000)  

• N. Malmstadt, et al., “A Smart Microfluidic Affinity Chromatography Matrix Composed of Poly (N-isopropylacrylamide)-Coated Beads”, Anal Chem, 75, 2943-2949 (2003)

• N. Malmstadt, et al, “Smart Mobile Affinity Matrix for Microfluidic Immunoassays”, Lab   

Chip, 4, 412-415 (2004)

• M. Ebara, et al., “Switchable surface traps for injectable bead-based chromatography in PDMS microfluidic channels”, Lab Chip, 6(7), (2006)

• M. Ebara, et al. “Surface Modification of Microfluidic Channels by UV-mediated Graft Polymerization of Non-fouling and ‘Smart’ Polymers” Radn  Phys & Chem 76, 1409?1413 (2007)

• R. Narain, et al., "Synthesis of Monodisperse Biotinylated p(NIPAAm)-Coated Iron Oxide Magnetic Nanoparticles and their Bioconjugation to Streptavidin", Langmuir, 23, 6299-6304 (2007)

• J. Lai, et al. “Dual Magnetic-Temperature Responsive Nanoparticles for Microfluidic Separations and Assays”, Langmuir, 23, 7385-7391 (2007)

报告人简介：

Professor Allan S. Hoffman

Education:

B.S., M.S., and Sc.D. degrees in Chemical Engineering at MIT, between 1953 and 1957. 

Professional Experience:

Professor Hoffman taught on the faculty of M.I.T. Chemical Engineering Department for a total of ten years.  Since 1970 he has been Professor of Bioengineering at the University of Washington in Seattle, Washington.

Other Recognitions and Awards:

•President, Society for Biomaterials, 1983-1984

•Biomaterials Science Prize, Japanese Biomaterials Society, 1990

•Founders’ Award of the Society for Biomaterials, 2000

•Elected to the National Academy of Engineering, 2005

•International Award from Society for Polymer Science, Japan, 2006

•Founders Award of the Controlled Release Society, 2007