Automation of enzyme assays.

The increasing use of enzymes as aids to clinical diagnosis has made it mandatory for clinical biochemists to develop techniques and instrumentation to enable large numbers of specimens to be processed quickly with adequate accuracy. The main objective in enzyme assay is to determine the initial reaction rate, as it is only during this period that there is a linear relationship between the rate and enzyme concentration. There are four approaches to rate measurements which are given in Table I. In practice it is normal for most enzyme estimations to be made by the first and third of these, the fourth being only applicable to enzyme systems where changes in acid or base are to be monitored. Schwartz and Bodansky (1963) have defined three stages of automation dependent upon the degree of automation of the assay procedure (Table II). Even with stage I automation there are means of work simplification which increase the capabilities of the technique. In the present discussion a variety of