Evaluation of homogeneous enzyme immunoassay of serum thyroxine with use of bichromatic analysis.

We evaluated the homogeneous enzyme immunoassay ("EMIT") of serum thyroxine with use of an ABA- 100 Bichromatic Analyzer, modified with an auxiliary dispenser syringe and a dual probe assembly. The modification allows two reagents to be dispensed at one time. The sera must be pre-treated with 0.1 mol/liter NaOH. The procedure thereafter is entirely automated. Twenty-four patients' samples may be analyzed in 15 min of instrument time. Precision and accuracy are excellent, and results correlate well with those by radioimmunoassay.