We show how the controlled modification of material surfaces by ion beams may lead to biological applications ranging from biocompatible materials to biosensors and biological devices. Specifically, the present chapter addresses the use of low- and medium-energy ion beams to modify polymer surfaces. We provide a short introduction to those surface properties that determine the biological response and summarize basic features of ion-surface interaction processes in polymers, emphasizing the relation between ion irradiation and surface-property modification: the adsorption/organization processes of amino acids, peptide sequences, proteins and cells are all influenced by ion-irradiation treatments. The possibility of obtaining controlled interactions of biological systems (e.g., amino acids, peptide sequences, proteins and cells) with beam-modified polymers is described in terms of a few well-defined surface properties. These include the surface free energy (SFE), the surface morphology and topography, the surface polarity, surface termination and the mechanical properties of the outermost surface layers. In this context, the concept of "biocompatibility" is briefly explained as the ability of a material to provide specialized addressing of biological functions, including a message that a biological system can perceive as a proper "signaling mode" to prompt its appropriate response. Finally, the relevance of ion beams to induce spatially resolved adsorption/adhesion processes in biological systems is demonstrated: the scales range from tens of nanometers to tells of micrometers. The emphasis is on achieving nano(or micro)sized patterns of biological molecules to produce bioelectronics devices. Some examples are given of potential ion-beam applications in manipulating the organization of biological systems on surfaces.
|Titolo:||Ion-Beam Modification of Polymer Surfaces for Biological Applications|
|Data di pubblicazione:||2010|
|Appare nelle tipologie:||1.1 Articolo in rivista|