“Nanotexturing of Drug-Eluting Stents for Preventing Thrombosis”
Dr. Palaniappa Molian, Iowa State University
The drug-eluting stent (DES), invented in 2003, is widely used in interventional cardiology to prevent restenosis (narrowing of an artery) and myocardial infarction (heart attack). A critical issue with a DES is the development of thrombosis (blood clotting) over time, leading to delayed healing, hypersensitivity reaction and potential mortality among patients. Thrombosis is attributed to the rapid depletion of DES drug coating and the degradation of the polymer used as a carrier for the drug. A novel concept of nanoscale structures such as protrusions and ripples on the surfaces of stents to store and hold the drug for longer periods and enhance the adhesion of the drug to the stent without the need for a polymer carrier is conceived. Ultrafast laser nanotexturing of a Nitinol platform DES prior to the application of drug/polymer was conducted to demonstrate the proof of concept. The significance of the project is twofold: one is to increase the production rate and reduce the cost in the $7 billion a year DES market by changing the supply chain of DES fabrication; and second is the development of a long-lasting, safe and polymer-free DES to enhance the health of patients such that they enjoy the important possibilities of life.
The seminar will begin with a brief overview of the speaker’s research program in the field of advanced manufacturing and the associated state-of-the-art laboratory facility. Preliminary results of the effects of nanotexturing on the surface morphology, hydrophobicity, drug adherence with and without polymer, and the drug elution profile of DES will then be described. The laser-material interaction phenomena in ultrafast regime coupled with process validation and verification to ensure repeatability and reproducibility of nanotexturing will be discussed. Finally future opportunities and challenges of micro/nano-manufacturing technologies for medical devices, microelectronics and MEMS, and the benefits for the state of Texas and beyond will be presented.
Palaniappa Molian is a professor of mechanical engineering at Iowa State with expertise in advanced manufacturing. He is one of the pioneers of laser materials processing technology. His research interests include micro/nano-manufacturing, biomedical manufacturing and MEMS. He holds a doctorate from Oregon Graduate Institute of Science and Technology. During the past three years he has published 30 journal papers and received funding for five NSF projects. He has been the thesis adviser for more than 50 graduate students. He has developed a world-class laboratory for lasers, MEMS and nanotechnology at Iowa State, and he has actively participated in numerous industrial projects, including federally funded SBIRs.