antibody to detect FLAG® conjugated proteins is shown to detect as little as 3 ng of amino-terminal FLAG® tagged recombinant protein by western blot. This antibody was used at a 1:1,000 dilution to detect 3-fold serial dilutions of amino-terminal FLAG®-Bacterial Alkaline Phosphatase (BAP) fusion protein (Sigma P-7582) starting at 1.0 µg of protein as shown in lanes 1-6 respectively. A 4-20% gradient gel was used to separate the protein by SDS-PAGE. The protein was transferred to nitrocellulose using standard methods. After blocking, the membrane was probed with the primary antibody for 1 h at room temperature followed by washes and reaction with a 1:10,000 dilution of IRDye® 800 conjugated Gt-a-Rabbit IgG (H&L) for 30 min at room temperature. LICOR's Odyssey Infrared Imaging System was used to scan and process the image. Other detection systems will yield similar results.