Gold Nanoclusters with Strong near Infrared Absorbance for Biomedical Imaging

Thursday, October 20, 2011: 4:30 PM
205 C (Minneapolis Convention Center)
Ameya U. Borwankar1, Brian W. Willsey2, Tianyi Wang3, Veronika Sapozhnikova4, April Twu1, Marc D. Feldman5, Thomas E. Milner3 and Keith P. Johnston1, (1)Chemical Engineering, University of Texas at Austin, Austin, TX, (2)Dept. Materials Science, University of Texas at Austin, Austin, TX, (3)Biomedical Engineering, University of Texas at Austin, Austin, TX, (4)South Texas Veterans Affairs Hospital System, San Antonio, TX, (5)Division of Cardiology, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX

We have developed small 40-50 nm gold nanocluster NIR imaging agents, stabilized by carboxymethyldextran (CMD) The shape asymmetries and the closely spaced primary particles within the clusters  produce a strong near infra red (>800 nm) absorbance via a surface plasmon resonance (SPR), as a result of multipole interactions. The cluster size was characterized by dynamic light scattering(DLS) and TEM, whereas the quantity of polymer was determined by Thermogravimetric analysis. We develop a theory to explain the synthesis of these particles based on nucleation, clustering and growth upon reduction of a Au precursor in the presence of CMD. Molecular imaging of plaque in coronary arteries before rupture is a crucial step in treating atherosclerosis. These particles are preferentially engulfed by macrophages associated with vulnerable plaque due to the CMD associated with the particles. The particles also exhibit multi-photon luminescence and hence the plaque can be imaged by multi-photon microscopy.

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See more of this Session: Nanotechnology for In Vivo and In Vitro Imaging
See more of this Group/Topical: Nanoscale Science and Engineering Forum