IEC 82 |
| Ashutosh Chilkoti, Department of Biomedical Engineering, Department of Biomedical Engineering, Duke University, Box 90281, Durham, NC 27708 |
| We report two different applications of the optical transduction exhbited by noble metal nanoparticles. We have explored the use of gold nanoparticles in suspension as a colorimetric reporter of the interfacial phase transition of a class of stimuli responsive biopolymers, termed elastin-like polypeptides (ELP). We observed that gold nanoparticles, onto which an ELP is immobilized, exhibit a large red-shift in their absorbance spectrum due to aggregation of the nanoparticles, driven by the hydrophilic-to-hydrophobic phase transition of the immobilized ELP. This method provides a simple and convenient colorimetric method to study the influence of the solution environment, interfacial properties and grafting method on the transition properties of environmentally responsive polymers at the solid-water interface. We have also immobilized gold nanoparticles onto glass slides, functionalized these surface with biological ligands, and shown that these colloid-decorated surfaces enable ligand-binding to be detected by the shift in the absorbance spectrum of individual colloids. This assay is analogous to conventional SPR with the added advantage of being performed in widely available, low-cost UV-visible spectrophotometers. |
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Nanoscale Sensing Technology: Why and How? (sponsored by Advanced Materials & Nanotechnology Subdivision)
2:00 PM-5:05 PM, Monday, March 24, 2003 Convention Center -- Room 394, Oral
Division of Industrial and Engineering Chemistry |