AVS 50th International Symposium
    Biomaterial Interfaces Tuesday Sessions
       Session BI-TuP

Paper BI-TuP2
Plasma Processing pf Polymers to Reduce Bio-Fouling for Cardiac Applications

Tuesday, November 4, 2003, 5:30 pm, Room Hall A-C

Session: Poster Session
Presenter: M. Neumann, University of Illinois at Urbana-Champaign
Authors: M. Neumann, University of Illinois at Urbana-Champaign
P. Fackler, University of Illinois at Urbana-Champaign
D.N. Ruzic, University of Illinois at Urbana-Champaign
Correspondent: Click to Email
Polymers are playing an increasing role in cardiac medicine as components of implants and diagnostic devices, such as tubes, diaphragms, filters, pacemaker components, blood bags, sutures, vascular grafts and shunts. Polymers exhibit high strength to weight ratio, wide range of flexibility, ease of formability, and economics of production, but processes designed to achieve desired surface properties can compromise the overall bulk material. The ability to alter the surface of the polymer while leaving the underlying bulk material unchanged has a large potential for development in the area of biomaterials. Modifying the surface of a polymeric material so as to impede water adhesion and the ability of proteins, bacteria, and cells to grow on the surface can be minimized on those surfaces that are incorporated into biological systems. This can minimize infection, thrombosis, and other undesirable interactions. Polymer surface modification was accomplished via plasma etching and deposition in a commercial size plasma-etching device, which achieves plasma densities and electron temperatures up to 10@super 11@ cm@super -3@ and 4 eV. The degree of change is controlled by macroscopic external controls, rather than invasive internal modifications. This process lends itself well for use in existing systems. Water contact measurements taken before and after treatment of HDPE that show a change from a pretreatment angle of 85° to post treatment angles of 5°, which corresponds to a dramatic change in surface energy of the polymer and biological interaction potential. This modification is both physical and chemical, but limited to a few microns of the surface of the material. Plasma analysis is done through use of Langmuir probes, microwave interferometery, and optical spectroscopy. Surface analysis is done through XPS. Blood-material interactions are studied through two-dimensional electrophoresis in order to determine the extent and nature of protein coverage.