Plasma-polymerized thin film for biosensors of a new generation

A biosensor is a device that converts information on the concentration of chemical or biochemical substances into a quantifiable electronic signal. The typical structure of a biosensor is an integrated product utilizing biological components and transducers. We have indicated that plasma-polymerized thin films have potential for use in the interfacial design between these two components for biosensors. A plasma-polymerized film was achieved in a plasma in the vapor phase. The properties of the film are that they: (i) are extremely thin (<1 μm), (ii) provide good adhesion to the substrate, (iii) are pin-hole free and present a flat surface structure, (iv) are mechanically and chemically stable because of the highly branched and cross-linked structure in the polymer, and (v) allow for large amount of biological components, such as enzymes and antibodies, to be loaded onto the surface of the film. Recently, the trend in biosensors can be addressed concerning two main aspects. One is a micro total analytical system and/or a micro electro mechanical system, which is an analytical system integrated into one chip in order to reduce the solvent, the amount of the sample, and the time and cost of analysis, The other is a post genome research tool, such as a DNA or a protein chip; the former allows an easy and rapid analysis for gene expression and single-nucleotide polymorphism; the latter allows proteome analysis e.g., a capillary electrophoresis chip and analysis for biospecific interaction. In this article, we stress the usefulness of plasma-polymerized films and/or a process for a new generation of biosensers.