CEDIA--homogeneous immunoassays for the 1990s and beyond.

New homogeneous enzyme immunoassays have been developed for cortisol, digoxin, digitoxin, theophylline, phenytoin, and phenobarbital using the cloned enzyme donor immunoassay technology. As applied to Boehringer Mannheim/Hitachi analysis systems these methods provide rapid, accurate and precise quantification of analytes, with minimal interferences from endogenous serum constituents and low cross-reactivities to structurally-related hormonal precursors, drug metabolites and natural compounds. Additional significant features of the new assays are linear standard curves and two-point calibration. The six CEDIA assays join the two currently available CEDIA assays for determination of the thyroid parameters T4 and T Uptake. Additional new therapeutic drug and anemia monitoring assays are under development, demonstrating the versatility of the cloned enzyme donor immunoassay technology. These tests, in concert with Boehringer Mannheim/Hitachi analyzers, provide a high throughput, random access immunoassay system. The menu of available assays should continue to increase during the 1990s, providing efficient automation while allowing consolidation of testing on a limited number of instrument systems.