Sarcosine is a nonprotein amino acid and a structural isomer of alanine. While alanine is chiral, sarcosine is achiral since it does not have an asymmetric carbon atom. Its molecular structure is CH3NHCH2COOH, and its molecular weight is 89.093. Though sarcosine is not a protein amino acid, it is a biogenic amino acid and is widely distributed in organisms. It is widely distributed in foods such as egg yolks, meats, and vegetables. Since it has no amino group (-NH2) but an imino group (-NH-), it requires special care in amino acid analysis, since sensitive amino acid detection often requires derivatization of the amino group. It is one of the most abundant amino acids in prebiotic chemistry. Sarcosine was found in Miller’s spark discharge products and also in extracts from carbonaceous chondrites such as the Murchison meteorite.