Microdetermination of serum D-amino acids.

A method for the quantitative determination of serum D-amino acids in the range 0.5-20 nmol is described. In the method alpha-keto acids, derived from D-amino acids by D-amino acid oxidase, are measured as hydrazones. The method is unresponsive to the presence of a large excess of L-amino acids. It allows a fast assay in a small amount of specimen (0.1 ml), with good reproducibility and accuracy.