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Novel Polymer Microgel Dispersions with an Inverse Thermoreversible Gelation Zhibing Hu, University of North Texas, DMR 0507208.
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Novel Polymer Microgel Dispersions with an Inverse Thermoreversible GelationZhibing Hu, University of North Texas, DMR 0507208 Left: Temperature dependence of loss tangent (tan(δ) = G′′/G′) at various oscillatory frequencies. The polymer concentration of IPN microgel dispersion is 3.0 wt % at pH 7. The dispersion of microgels with two interpenetrating polymer networks of poly(N-isopropylacrylamide) and poly(acrylic acid) (PNIPAM-IPN-PAAc) has been studied for its viscoelastic behavior, biocompatibility, and in vivo release properties. The gelation temperature was determined to be 33 °C at the point where a frequency-independent value of the loss tangent was observed. Using an animal implantation model, the biocompatibility and drug release properties of the IPN microgel dispersion were evaluated. Biomacromolecules9, 142, 2008. Fluorescence images of the tissues reveal that a small amount of residual fluorescein as a modol drug was present in the fluorescein-injected tissue (top left) and large amount of fluorescein still reside in the PNIPAM-IPN-PAAc microgel dispersion implanted tissue after 24 hours (top right).
Novel Polymer Microgel Dispersions with an Inverse Thermoreversible GelationZhibing Hu, University of North Texas, DMR 0507208 Education Two graduate students and one undergraduate student are working on this project. P. Kendall, an undergraduate student sponsored by NSF’s REU program, has worked on this project in summer 2007. He presented his results at the 2007 Fall Texas Section Meeting of the American Physical Society, October 18–20, 2007, College Station, Texas. Outreach The PI has performed physics demonstrations for undergraduate students, pre-college teachers, young people, and other non scientist members of the public. Hosted two students of the Texas Science and Mathematic Academy (TAMS) at UNT. They have gained research experience in polymer physics. Based on their innovative research in our lab, E. Chen was named as a Siemens Westinghouse competition semifinalist (2007). S. Thompson was named as a Siemens Westinghouse competition semifinalist and regional finalist (2007), and an Intel science talent search semifinalist (2007). Thompson's research also led to his winning a Barry M. Goldwater Scholarship.