Amino acid analysis.

Amino acid analysis of synthetic peptides is a robust and highly reliable analytical technique. For HPLC-purified peptides, absolute recovery accuracies of better than 5% are readily attainable. The presence of scavengers and incompletely cleaved protecting groups can have a significant impact on the quality of data that is obtained from crude samples. It should still be possible to obtain a reasonably accurate estimate of the quantity of the synthetic product, but the recovery of some amino acids can be compromised at times. When amino acid analysis is used in conjunction with mass spectrometry and a quantitative separation technique such as HPLC or CE, it can contribute significantly to the complete characterization of a synthetic peptide preparation.