Santa Cruz Biotechnology offers a variety of tissue extracts, whole cell lysates and nuclear extracts for use in combination with our antibodies as Western Blotting or Immunoprecipitation positive controls. Our nuclear extracts are suitable as either positive controls for Western Blotting or for use in Gel Shift Assays. For use as positive controls for phospho-specific antibodies, we offer Phospho-Enriched Whole Cell Lysates and Tissue Extracts.