Ion beam techniques for biomedical applications

  • Venue:

    KIT - Campus South -
    Seminar Room 1004/105, Bldg. 30.25

  • Date:

    06.11.2009

  • Speaker:

    Dr. Somjai Sangyuenyongpipat-Isotalo
    Accelerator Laboratory, Dept. of Physics
    Univ. of Jyvaskyla, Finland

  • Time:

    14:30

  • Abstract:

    Gene Transfer. Ion beam bombardment of biological material has been recently applied for gene transfer in both plant and bacterial cells. Understanding of the fundamental mechanisms involved in ion interaction with living cells is not yet well developed. A fundamental question about the mechanism is the possible formation of pathways due to ion bombardment that are responsible for the gene transfer. Low energy bombardment of onion skin cells with both metallic and gaseous ion species at fluences of 1–5 ×1015 ion/cm2, can induce the formation of microcrater-like structures on the onion skin cell walls. An in-situ atomic force microscope (AFM) has been developed to observe these microcrater structures.
    Neuroscience. The use of metal ion implantation using a vacuum-arc ion source and plasma deposition with a filtered vacuum arc system which is the other interesting example of how to use ion beam techniques as a tool for neuroscience, has been investigated as a means of forming regions of selective neuronal attachment on surfaces. PC-12 rat neurons were then cultured on treated glass slides coated with Type I Collagen, and the neuron growth and differentiation monitored. Thin diamond-like carbon films formed by plasma deposition were found to be the most effective for selective neuron growth.
    Lithography. A novel and flexible MeV ion beam lithography technique utilizing a 1.7 MeV Pelletron accelerator has been recently developed in the Accelerator Laboratory, University of Jyvaskyla. The high-energy ion beams are capable of direct-writing three-dimensional (3D) patterns with straight vertical sidewalls in polymers (e.g. PMMA) up to 50µm thick. The rectangular beam spot is defined by the shape of a computer-controlled variable aperture, the Programmable Proximity Aperture Lithography (PPAL), which is placed in close proximity to the polymer sample. The main thrust of the work is for several specific biomedical applications at the cellular and sub-cellular level such as developing cell growth substrates for study of the dynamics of bone development, cell spotting plates, high-aspect ratio plasma etching for master stamps, and more.