Product Description

Immunoglobulin G (IgG) is the most abundant antibody isotype in serum, playing central roles in humoral immunity. IgG is mainly produced by plasma cells and functions to neutralize pathogens, opsonize for phagocytosis, activate the classical complement pathway, and cross the placenta to provide passive immunity to the fetus. Human IgG comprises four subclasses (IgG1–IgG4) with distinct effector functions. Dysregulation of IgG is associated with various diseases: pathogenic autoantibodies appear in autoimmune diseases, whereas IgG subclass deficiencies lead to increased susceptibility to infections. Consequently, intravenous immunoglobulin (IVIG) is used to treat immunodeficiencies and autoimmune diseases, underscoring the critical role of IgG in both immune defense and pathology.

Screeningbio’s TR-FRET Human IgG Detection Kit is designed for the quantitative determination of human IgG concentrations in cell culture supernatants or purified samples. This kit employs a sandwich immunoassay format based on TR-FRET technology, offering features such as simplicity, rapidity, high accuracy, and good reproducibility.

The basic principle of this method is illustrated in the figure on the right. Solar Eu‑labeled anti‑human IgG Fc antibody and LA‑labeled anti‑human IgG Fab antibody are brought into proximity upon binding to human IgGs. When the dye labels on the antibodies are in close proximity, fluorescence resonance energy transfer (FRET) occurs. As the concentration of standards or samples increases, the TR‑FRET signal intensity increases proportionally, meaning that the concentration of standards or samples is directly proportional to the signal intensity.