title: Simultaneous topographic and amperometric membrane mapping using an AFM probe integrated biosensor.
abstract: The investigation of the plasma membrane with intercorrelated multiparameter techniques is a prerequisite for understanding its function. Presented here, is a simultaneous electrochemical and topographic study of the cell membrane using a miniaturized amperometric enzymatic biosensor. The fabrication of this biosensor is also reported. The biosensor combines a scanning force microscopy (AFM) gold-coated cantilever and an enzymatic transducer layer of peroxidases (PODs). When these enzymes are brought in contact with the substrate, the specific redox reaction produces an electric current. The intensity of this current is detected simultaneously with the surface imaging. For sensor characterization, hydroquinone-2-carboxylic acid (HQ) is selected as an intrinsic source of H(2)O(2). HQ has been electrochemically regenerated by the reduction of antraquinone-2-carboxylic acid (AQ). The biosensor reaches the steady state value of the current intensity in 1 ± 0.2s.
authors.affiliation: Institute of Photonic Technology, Albert-Einstein-Straße 9, 07745 Jena, Germany. sarmiza.stanca@mti.uni-jena.de
authors.forename: Sarmiza Elena
authors.initials: SE
authors.lastname: Stanca
authors.forename: Andrea
authors.initials: A
authors.lastname: Csaki
authors.forename: Matthias
authors.initials: M
authors.lastname: Urban
authors.forename: Sandor
authors.initials: S
authors.lastname: Nietzsche
authors.forename: Christoph
authors.initials: C
authors.lastname: Biskup
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Fritzsche
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D016466:CHO Cells; D002462:Cell Membrane / Q000737:chemistry* / Q000648:ultrastructure*; D006224:Cricetinae; D003412:Cricetulus; D055664:Electrochemical Techniques; D004800:Enzymes, Immobilized; D004867:Equipment Design; D006046:Gold; D006873:Hydroquinones / Q000737:chemistry; D018625:Microscopy, Atomic Force / Q000295:instrumentation* / Q000379:methods; D010084:Oxidation-Reduction; D010544:Peroxidases
chemical_list: D004800:Enzymes, Immobilized; D006873:Hydroquinones; D006046:Gold; D010544:Peroxidases