A polypeptide, preparation and use thereof

The present invention discloses a polypeptide, preparation method and application. The polypeptide having the following amino acid sequence: R1-Arg-Val-Tyr-Val-His-Pro-Phe; wherein, R1 is Asp, isoAsp or Ac-Asn. Polypeptide of the present invention are prepared in the process of angiotensin three key impurities, it may be used as a standard reference detection process angiotensin, angiotensin, and qualitative and quantitative analysis of impurities, for improving the quality standards of angiotensin , product quality control is important.