Electrophysiology equipment and software

There is a wide range of methods available for the study of ion transport across biological membranes. Early, simple measurements of pH and ion concentrations resulted in striking insights, such as the chemiosmotic theory ( Mitchell, 1961 ) and, for plant nutrition, the discovery of low- and high-affinity systems for potassium uptake ( Epstein et al ., 1963 ). Modifications to these techniques (radioactive tracers, fluorescent probes, etc.) have enabled better temporal and spatial resolution of such ion transport mechanisms. However, some of the most important breakthroughs have come with the advent of the voltage clamp ( Cole, 1949 ; Cole & Moore, 1960 ) and, subsequently, with the development of the patch clamp ( Neher & Sakmann, 1976 ; Hamill et al ., 1981 ). The theory and applicability of the voltage clamp are discussed in the previous chapter; in this chapter, we discuss some important practical aspects of the techniques involved and present an overview of some of the equipment and computer software available to researchers in this field.