Reagentless biosensors based on mediator-modified electrodeposition hydrogels
|Wolfgang Schuhmann 1, Dmitrii Guschin , Bertrand Ngounou , Artjom Maljusch , Sandra Janiak , Stephanie Möller , Leonard Stoica|
1. Ruhr-Universität Bochum, Anal. Chem. - Elektroanalytik & Sensorik (ELAN), Universitätsstr. 150, Bochum 44780, Germany
Recently, the electrochemically-induced selective modification of electrode surfaces by means of electrodeposition hydrogels under simultaneous entrapment of biological recognition elements was reported . This method is based on an electrochemically-induced pH-modulation within the diffusion zone caused by the oxidation or reduction of water concomitantly modulating the solubility of the polymer chains. This change in solubility causes the precipitation of the polymer exclusively on the electrode surface. In the presence of a suitable enzyme the biological recognition element is entrapped within the precipitating polymer film and by this securely immobilized on the electrode surface. The synthesis of electrodeposition paints enables on the one hand the adaptation of the properties of the deposited polymer film to the specific needs of the entrapped biological recognition elements. On the other hand, specific functionalities may be integrated for further polymer crosslinking, attachment of redox mediators etc. The tutorial lecture will be directed to the specific considerations in the development of reagentless amperometric biosensors. Especially, the design of electron-transfer pathways between polymer-entrapped redox proteins and the electrode surface will be discussed in detail . Based on this background, recent work concerning the application of redox-modified electrodeposition hydrogels will be described and the points will be discussed in detail: (i) synthesis of monomers for the coordinative binding of metal complexes; (ii) synthesis of libraries of electrodeposition paints and their modification with redox relays; (iii) voltammetric characterization of the obtained redox polymers; (iv) possibilities for varying the redox potential of the redox hydrogel; (v) automatic optimization of related reagentless biosensors using an automatic electrochemical robotic system; (vi) integration of PQQ-dependent dehydrogenases within redox relay modified electrodeposition paints; (vii) multi-layer multi-enzyme biosensors.
 (a) C. Kurzawa, A. Hengstenberg, W. Schuhmann, Anal. Chem., 74 (2002) 355 (b) B. Ngounou, S. Neugebauer, A. Frodl, S. Reiter, W. Schuhmann, Electrochim. Acta, 49 (2004) 3855.
Acknowledgement: Financial support from the EU (INTAS 01-2065 and INTAS 03-51-6278) is acknowledged.
Presentation: Tutorial lecture at SMCBS'2005 Workshop, by Wolfgang Schuhmann
See On-line Journal of SMCBS'2005 Workshop
Submitted: 2005-07-22 17:13 Revised: 2009-06-07 00:44