Anti-β-Actin (4D3) Antibody

This mouse monoclonal antibody from Antibodies.com is raised against the cytoskeletal housekeeping protein β-actin (~42 kDa) and is supplied as the well-characterized clone 4D3. The unconjugated reagent is provided as 100 µl of liquid at 1 mg/ml in phosphate-buffered saline (PBS) containing 15 mM sodium azide at approximately pH 7.2, ready for direct labeling or for use with a secondary antibody of choice.

Validated applications include Western blot (WB) and immunohistochemistry (IHC), so the antibody is suited for confirming equal protein loading across lanes and for visualizing actin-rich structures in fixed tissue sections. It cross-reacts with β-actin from human, mouse, and rat, with broader reactivity reported across mammalian species. Because β-actin is constitutively expressed in most cell types, it is commonly used as an internal loading reference alongside target-specific primary antibodies in parallel Western blot runs.

Upon receipt, aliquot the vial and refrigerate for short-term use or freeze for longer-term storage. Avoid repeated freeze-thaw cycles and protect the antibody from prolonged light exposure. Sodium azide is included as a preservative; handle accordingly for downstream in vitro and live-cell work. Each 100 µl vial at 1 mg/ml provides ample material for many standard immunoblotting and staining experiments.