Simple and rapid estimation of serum theophylline concentration using apoenzyme reactivation immunoassay

Theophylline concentration was measured by the apoenzyme reactivation immunoassay system using the Seralyzer system. The results were compared with those obtained employing high performance liquid chromatography and substrate-labelled fluorescent immunoassay. The results obtained by the above three methods were quite compatible with each other. Furthermore, the capillary method was quite compatible with the venous method which is useful for frequent measurement of theophylline concentrations, especially in children with asthma.