Assay of phenobarbital: adaption of "EMIT" to the centrifugal analyzer.

We have adapted the centrifugal analyzer to the homogeneous enzyme immunoassay ("EMIT") for phenobarbital. The assay was modified to give greater range and sensitivity, and less reagent is needed. The transfer disc is prepared with totally automatic pipetting. Results are calculated with a micro-computer that provides a logit transformation of absorbance data. Precision and accuracy are excellent, and results correlate well with those by gas-liquid chromatography.