Anti-GPx4 Antibody - Western Blot. Western blot of affinity purified anti-GPx4 to detect GPx4 in testis extract (arrow). tissue extract (40 ug) was electrophoresed and transferred to nitrocellulose. The membrane was probed with the primary antibody at a 1:1000 dilution. Personal Communication, Dolph Hatfield, CCR-NCI, Bethesda, MD.