Anti mrp1 antibody

Cells were lysed in cold RIPA lysis buffer with protease/phosphatase inhibitor cocktail (Roche, Indianapolis, IN, USA) for whole cell lysates. A cell fractionation kit (CST, Danvers, USA) was used to isolate cell membrane protein. Cell membrane protein was collected for MRP1 detection. Protein (5–50 μg) was loaded in a mini gel (4% stacking, 8% separating SDS-PAGE). After separation, gels were transferred to a nitrocellulose membrane (Bio-Rad, Hercules, CA, USA). Membranes were blocked using 5% non-fat milk in TBS buffer, then incubated at 4°C with the respective primary antibody overnight; anti-BCRP primary antibody (Abcam, Cambridge, UK, 1:2000), or anti-MRP1 antibody (Abcam, Cambridge, UK, 1:25). Whole cellular protein was normalized using β-Actin (Cell Signaling Danvers, MA, USA, 1:2000). Membrane protein was normalized using a Na-K-ATPase antibody (Abcam, Cambridge, UK, 1:2000). The secondary antibody (IRDye® 800CW goat anti-rabbit or IRDye^® 680RD Goat anti-Mouse (1:15,000)) was incubated in the dark at room temperature for 45 min. Dual-channel infrared scan and quantitation of immunoblots were conducted using the Odyssey Sa infrared imaging system with Image Studio (Ver. 3.1.4) (LI-COR, Lincoln, NE, USA).