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IMNI Awards Summer Internships       
June 2008

IMNI offers to support two undergraduate interns over the summer to work on collaborative interdisciplinary or multidisciplinary projects in the molecular and nanosciences.
        

Text Box: IMNI Summer Scholar Alexandra Witthoft graduated this May from Mt. Holyoke College, and within two weeks, she was at Brown working with Assistant Professor Rashid Zia. Her research project investigates how the microscopic response of individual rare earth ions might contribute to a new class of optical materials which demonstrate atomic, optical frequency magnetism.   During past summers, Alix has participated in REU programs at Yale and University of Rochester where her work focused upon granular materials and astronomy. She sees this IMNI Summer Scholarship as a unique opportunity to merge her interest in optics and material science by exploring nanoscale optical composites.   And starting this September, Alix hopes to use this summer research as the basis for her graduate studies, when she joins the Ph.D. program in the Division of Engineering at Brown.

 

Text Box: Margaret Merritt ‘11 was awarded the IMNI Summer Internship to work with Professor Tom Webster, et.al. on “Metallic Nanofeatures for Improving Vascular Stent Efficacy”  Margaret spent her summer developing a vascular flow system investigating endothelial cell (cells that line the vascular) functions on metal (specifically, titanium, nitinol, and stainless steel) stent surfaces modified to possess nanoscale surface features. Results from this summer project have been significant to Webster’s research efforts as it has supplied preliminary data that can be used for future proposals and also bring together a new group of researchers to tackle this significant problem with vascular stents that requires a multidisciplinary approach.   To see the abstract that Margaret is presenting to the Biomedical Engineering Society click here.

The Effects of Physiological Flow on Endothelial Cell Function on Nanostructured Coated Vascular Stent Materials
Margaret Merritt1, Jing Lu1, Karen M. Haberstroh1, and Thomas J. Webster1
1Department of Biomedical Engineering, Brown University, Providence, RI, USA

Abstract:
Titanium and stainless steel are widely used in vascular stent design.  Unfortunately, these materials have suffered from problems including stent migration and restenosis.  Therefore, the present study investigated properties of novel nanostructured coatings on titanium and stainless steel for improving vascular stent efficacy. To test cell density on these nanostructured coated materials, rat aortic endothelial cells (RAEC; Vec Technologies) were pre-seeded at 3,500 cells/cm2 for a 24-hour culture period. Samples and adherent cells were then transferred to fresh media and were cultured under static conditions for 4 additional hours. Adherent RAEC were stained, imaged using fluorescence microscopy, and counted.  Overall, the stainless steel nanostructured coating had the highest cell density compared to any other sample.  A traditional parallel plate flow chamber was further modified and used to analyze both coating strength and RAEC behavior under a flow environment. Preliminary results suggested that the stainless steel nanostructured coated remained in tact under physiological relevant flow conditions.  In summary, results of this study suggest that nanostructured coatings on stainless steel should be further studied for improving vascular stent efficacy. Such nanostructured coatings which promote endothelialization may reduce the need for stent drug elution which has been problematic as of late.