title: Electron transfer mediator micro-biosensor fabrication by organic plasma process.
abstract: We propose a new strategy for constructing a mediator-type biosensor as a Bio-MicroElectroMechanical Systems (BioMEMS) application. A vinylferrocene plasma-polymerized film (PPF) was deposited directly onto the surface of an electrode under dry conditions. The resulting redox film was extremely thin, adhered well onto a substrate (electrode), and had a highly crosslinked network structure. This technique, capable of polymeric deposition of any kind of monomer, can also serve the purpose of anti-fouling coating, or layer-to-layer interface creation. With a subsequent plasma process, additional polymeric layer of hydrophilic acetonitrile was superimposed onto the existing vinylferrocene-PPF surface to offer crucial features such that the wettability could be adjusted for a better electron transfer, and amino functional groups could be attached to immobilize a large amount of enzyme. Based upon this scheme, the device fabrication could be designed in a manner that the whole procedure was made up of dry wafer-handling processes, which is compatible with mass production. A prototype device was fabricated to have an array of needle-shaped amperometric micro-biosensors. The resultant thin polymer layer carried a large number of the mediator molecules, accomplishing a lower overpotential (+410 mV) and a rapid response time (<5s). Stressing the advantages of the plasma polymerization process together with some additional features accomplished in our device fabrication, we would discuss new possibilities in the field of BioMEMS.
authors.affiliation: Laboratory of Advanced Bioelectronics, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba-shi, Ibaraki 305-8562, Japan.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Hiratsuka
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Kojima
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Muguruma
authors.forename: Kyong-Hoon
authors.initials: KH
authors.lastname: Lee
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Isao
authors.initials: I
authors.lastname: Karube
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry; D003460:Crystallization / Q000379:methods*; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004579:Electron Transport; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005296:Ferrous Compounds / Q000737:chemistry*; D005740:Gases / Q000737:chemistry; D006358:Hot Temperature; D008839:Microelectrodes; D008904:Miniaturization; D009930:Organic Chemicals / Q000737:chemistry; D014753:Vinyl Compounds / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D003432:Cross-Linking Reagents; D005296:Ferrous Compounds; D005740:Gases; D009930:Organic Chemicals; D014753:Vinyl Compounds; C500579:vinylferrocene