Blockers Practical Guide

Blockers for Interference in IgM Capture Assays IgG Absorbent

IgG Absorbent is a purified goat anti-human IgG (GAH IgG Fc) Fc fragment designed for the removal of human IgG and IgG/rheumatoid factor (RF) complexes from serum prior to testing for specific IgM antibodies in ELISA or other immunoassays. Removal of IgG interference has been demonstrated to significantly increase the sensitivity of IgM detection in immunoassays. Meridian’s IgG Absorbent is tested by immunoelectrophoresis to ensure specificity for IgG and no cross-reactivity to IgM or IgA. Goat anti-human IgG (GAH IgG Fc) L15406G. IgM Assay Diluent IgM Assay Diluent is intended for use in qualitative and quantitative assays that detect IgM antibodies. This diluent is formulated to reduce assay interference from a patient’s IgG antibodies, rheumatoid factor, heterophilic antibodies, and other non-specific proteins that can affect the immunoassay results. Blocking proteins within the IgM Assay Diluent are in high excess and will bind to any open binding site on the assay solid phase to prevent binding from interfering factors. When included as a part of a test kit, IgM Assay Diluent can increase the sensitivity of an IgM detection assay. J82100B - ELISA Blocking Buffer (PBS, pH7.4) J82300B - Lateral Flow Blocking Buffer (PBS, pH 7.4) • Non-mammalian based blockers • Blocks non-specific binding to a solid phase subtrate to improve assay sensitivity • Stabilizes bound proteins on microplate/membrane • Increases signal-to-noise ratio • Use at 1x concentration or with further dilution Solid Phase Blocking Buffers

RECOMMENDED REAGENT: L15406G Goat anti-human IgG Fc (GAH IgG Fc) Dilute prior to adding to patient sample. Recommend diluting 1:10 in PBS.

A dd in a ratio of 1:10 to patient sample and allow to incubate 5-30 minutes.

RECOMMENDED REAGENT: 8120 IgM Assay Diluent

In a separate tube, dilute the patient serum sample in the IgM Assay diluent at a 1:21 dilution or greater (mix well). The diluent must be standardized with the other assay components.

J16430D - Coating Stabilizer and Blocking Buffer • Improves stability and function of antigens/proteins bound to a solid phase • Ideal for very unstable proteins or for less labile antigens/ proteins. Dilute up to 1:1 in the assay’s current blocker • Buffer pH 7.2 ± 0.2 A64801B - Bovine Serum Albumin (BSA) • Ideal for casein-sensitive antibodies, such as phospho-specific antibodies

• Can be used in ELISA, Western blot, and IHC • Use at 1-5% concentration in PBS at pH 7 • Lyopholized