Theoretical treatment of the amperometric current response of multiple microelectrode arrays

A theoretical approach to the steady-state limiting current response behavior of multiple microelectrode arrays, consisting of spherical, hemispherical, disk-shaped, or hemicylindrical electrode units, is presented. An approximative treatment is given for realistic arrays that contain microelectrodes of finite size and a rigorous description is offered for hypothetical arrays of point or line electrodes. The theories account for convection influences in the sample solution by restricting the diffusional mass transport of electroactive species between bulk sample and electrodes to a stagnant diffusion layer of variable average thickness. The parameters controlling the current efficiency of different arrays are discussed. The results show that arrays with a very low packing density of microelectrodes ideally yield the multiple response of a single microelectrode. The same behavior is generally found for interdigitated electrode arrays. In contrast, closely packed arrays of uniform electrodes simply mimic the response of a conventional macroelectrode of the same total surface area.

[1]  G. Veress,et al.  Modern trends in analytical chemistry , 1984 .

[2]  Koichi Aoki,et al.  Quantitative analysis of reversible diffusion-controlled currents of redox soluble species at interdigitated array electrodes under steady-state conditions , 1988 .

[3]  C. Kasper.  The Theory of the Potential and the Technical Practice of Electrodeposition I . The General Problem and the Cases of Uniform Flow , 1940 .

[4]  C. Nylander,et al.  Microstem electrodes : band ultramicroelectrodes fabricated by photolithography and reactive ion etching , 1991 .

[5]  Wilfried Mokwa,et al.  Ultramicroelectrode arrays as transducers for new amperometric oxygen sensors , 1992 .

[6]  Allen J. Bard,et al.  Electrochemical Methods: Fundamentals and Applications , 1980 .

[7]  John Crank,et al.  The Mathematics Of Diffusion , 1956 .

[8]  N. F. de Rooij,et al.  MICRO-ADAPTATION OF CHEMICAL SENSOR MATERIALS , 1995 .

[9]  A. Bard,et al.  Scanning electrochemical microscopy. 19. Ion-selective potentiometric microscopy , 1993 .

[10]  E. Wang,et al.  THEORY OF STEADY-STATE CURRENT AT MULTIPLE MICROCYLINDER ELECTRODES COUPLED WITH A PARALLEL PLANAR ELECTRODE , 1993 .

[11]  Allen J. Bard,et al.  Digital Simulation of the Measured Electrochemical Response of Reversible Redox Couples at Microelectrode Arrays: Consequences Arising from Closely Spaced Ultramicroelectrodes , 1986 .

[12]  Hisao Tabei,et al.  Electrochemical behavior of reversible redox species at interdigitated array electrodes with different geometries: consideration of redox cycling and collection efficiency , 1990 .

[13]  L. Anderson,et al.  Analytical strategies using interdigitated filar microelectrodes , 1990 .

[14]  C. Kasper.  The Theory of the Potential and the Technical Practice of Electrodeposition II . Point‐Plane and Line‐Plane Systems , 1940 .

[15]  Koichi Aoki,et al.  Time-dependence of diffusion-controlled currents of a soluble redox couple at interdigitated microarray electrodes , 1989 .

[16]  R. Wightman,et al.  Theory and experiment for the collector-generator triple-band electrode , 1991 .

[17]  B. Scharifker.  Diffusion to ensembles of microelectrodes , 1988 .

[18]  M. I. Montenegro,et al.  Microelectrodes : theory and applications , 1991 .

[19]  K. Tokuda,et al.  Voltammetry at partially covered electrodes: Part I. Chronopotentiometry and chronoamperometry at model electrodes , 1978 .

[20]  L. Anderson,et al.  Filar electrodes: steady-state currents and spectroelectrochemistry at twin interdigitated electrodes , 1985 .

[21]  R. Zwanzig,et al.  Chronoamperometric current at a random ensemble of microdisk electrodes , 1991 .

[22]  Christopher M.A. Brett,et al.  Electrochemistry: Principles, Methods, and Applications , 1993 .