Constraints of the MAX4781 CMOS Solution for Electrode Switching in Multilayer Electrochemical Probes

Abstract

The most common means to analyze redox gradients in sediments is by push/pulling electrochemical probes through sediment’ strata while repeating measurements. Yet, as electrodes move up and down they disrupt the texture of the sediment layers thus biasing subsequent measurements. This makes it difficult to obtain reproducible measurements or to study the evolution of electrochemical gradients. One solution for solving this problem is to eliminate actuators and electrode movements altogether, while instead deploying probes with numerous electrodes positioned at various depths in the sediment. This mode of operation requires electrode switching. We discuss an electrode-switching solution for multi-electrode probes, based on Complementary Metal-Oxide-Semiconductor (CMOS) multiplexors. In this solution, electrodes can be individually activated in any order, sequence or time frame through digital software commands. We discuss constraints of CMOS-based multilayer electrochemical probes during cyclic voltammetry.

Keywords

• sensor
• spear
• multielectrode
• redox interface
• sediments
• electrochemical gradients