Amino acid standards, physiological

The following components are included in the amino acid standard:
• L-Alanine
• Ammonium chloride
• L-Arginine
• L-Aspartic acid
• L-Cystine
• L-Glutamic acid
• Glycine
• L-Histidine
• L-Isoleucine
• L-Leucine
• L-Lysine
• L-Methionine
• L-Phenylalanine
• L-Proline
• L-Serine
• L-Threonine
• L-Tyrosine
• L-Valine
• β-Alanine
• L-α-Amino-n-butyric acid
• γ-Amino-n-butyric acid
• DL-β-Aminoisobutryic acid
• L-Anserine
• L-Carnosine
• L-Citrulline
• L-Creatinine
• Cystathionine
• Ethanolamine
• L-Homocystine
• δ-Hydroxylysine
• Hydroxy-L-proline
• 1-Methyl-L-histidine
• 3-Methyl-L-histidine
• L-Ornithine
• Sarcosine
• Taurine
• L-Tryptophan
• Urea 
Other Notes Amino acids and related compounds are 0.5 μmole/mL in 0.2 N lithium citrate, pH 2.2 containing 0.1% phenol and 2% thiodiglycol.