2784
Anal. Chem. 1985, 57,2764-2770
Voltammetry at Linear Gold and Platinum Microelectrode Arrays Produced by Lithographic Techniques Wolfgang Thormann, Peter van den Bosch, and Alan M. Bond* Division of Chemical and Physical Sciences, Deakin University, Waurn Ponds, Victoria 3217, Australia Gold and platlnum llnear voltammetrlc mlcroelectrode arrays constructed by llthographlc technology have been developed. This technology enables great versatlllty to be obtained wlth respect to number of senslng elements (3-256 used In thls work), size, and spacing. Individual elements are geometrlcally equlvalent to circular dlsk ultramicroelectrodes of radll 0.6-5 pm. Voltammetric measurements may be made at Individual senslng elements, part of the array, or the total llnear ensemble. The response of the array Is close, but not exactly equal, to the sum of the lndlvldual senslng elements. A steady-state voltammogram Is ylelded wlth current In the microampere range (oxldatlon of 1 mM ferrocene In acetonltrlle) for the larger arrays. All constructed ensembles exhlMt microelectrode characterlstlcs that permlt measurements to be made In the absence of dellberately added electrolyte. Addltlonally, translent technlques such as ac and pulse voltammetry can be applied wlth mllllsecond pulse widths In systems wlth supportlng electrolyte and wlth hlgh reslstance. Cornmerclally avallabie Instrumentation can readily be used wlth the larger arrays as Is demonstrated In thls work.
The behavior of microelectrodes with a surface area
