Potential applications and pitfalls of dry reagent tests. An evaluation of the Ames Seralyzer

In recent years, the development of dry reagent tests has made it possible for many clinical laboratory tests to be performed not only in the laboratory but also elsewhere. Some of the factors influencing the applications and use of one such system, the Ames Seralyzer, have been studied. Sample volume and the timing of analysis were critical, and poor precision was obtained by an inexperienced operator. The calibrators and reagent strips were stable when stored as recommended by the manufacturer, and calibration was stable for 24 hours. The implications of these findings as well as the problems of method comparison and quality control are discussed, particularly in relation to the use of the instrument outside the laboratory. More generally, this study illustrates several problems with the use of dry reagent, thin films and associated instrumentation that must be considered during evaluations.