The Guava RapidQuant™ Human IgG Kit provides quantitation of human IgG antibodies, typically found in hybridoma supernatants, using a bead-based assay followed by analysis on the Guava EasyCyte™ or EasyCyte™ Plus System. The kit contains IgG Capture Beads (Protein G-bound beads), which bind human antibodies (analyte) through the Fc region. The bound analyte is detected and quantitated using the FITClabeled goat anti-human IgG antibody provided in the kit. A human antibody standard (whole IgG), also provided with the kit, is used at different concentrations to obtain a standard curve. The kit quantitates IgG1, IgG2, IgG3, and IgG4 antibodies in the range of 0.5–20 μg/mL using the single standard provided. This kit works only with intact antibodies that include an Fc region. If the antibody to be tested is an F(ab')2, Fab, sFv, or other variant without an Fc region, this kit should not be used.