Good Old-Fashioned Protein Concentration Determination by Amino Acid Analysis.

Although a lot of new methods for protein concentration determination have been developed and established the last years, the amino acid analysis has still this relevance within proteomics for multiple reasons especially in the quantitative protein analysis. Amino acid analysis enables indirectly both the protein and peptide concentration determination which are essential for using the same amounts for comparative quantitative experiments. Moreover, the quantity and quality of synthetic peptides can be verified. The method itself is robust in comparison with colorimetric assays, especially when detergents or chaotropes are present in the sample buffer. Furthermore, it is highly sensitive. Nevertheless, amino acid analysis needs a certain experience to be set up and is time-consuming compared to other protein concentration determination techniques.