sh-Nonapeptide-11 SP is a single chain human peptide, produced synthetically to be identical to a portion of the protein, Alpha-1 Antitrypsin, and contains 9 amino acids consisting of aspartic acid, glutamic acid, glycine, isoleucine, leucine, lysine and threonine. Alpha-1-antitrypsin contains a maximum of 418 amino acids consisting of the proper sequence of the 20 standard amino acids.