Time-Resolved Immunofluorometric Assay for Human Interferon-γ

Abstract

A time-resolved Immunofluorometric assay (TR-IFMA) for interferon-γ (IFN-γ) was developed and its properties were compared with those of previously reported immunoenzymometric assays (IEMAs). The advantage of TR-IFMA is not only that it is as sensitive as the usual colorimetric IFMA, but that it is also feasible and fast as a detection procedure of europium. It was modified in order to make it more sensitive and faster by changing the antiserum and incubation conditions. The improved assay could directly measure IFN-γ in human plasma without any pretreatment. The detection limit for IFN-γ is 40pg/ml, and an assay can be completed within 6 h.