Fast and sensitive interferon-γ assay using supercritical angle fluorescence

Abstract

We present an immunoassay for Interferon-Γ (IFN-Γ) with a limit of detection of 1.9 pM (30 pg/mL) and a linear concentration range spanning three orders of magnitude. The developed one-step assay takes only 12 min and can replace the time-consuming and labor-intensive enzyme-linked immunosorbent assay (ELISA). The solid-phase sandwich assay is performed on a new measurement system comprising single-use test tubes and a compact fluorescence reader. The polymer tubes contain an optical configuration for the detection of supercritical angle fluorescence, allowing for highly sensitive real-time binding measurements. ©2013 by the authors; licensee MDPI, Basel, Switzerland.