Amino Acid Analysis

Importance of Amino Acids

Analysis of amino acids is required in several areas of research, and it is a fundamental tool in product analysis. The application imposes different requirements on the analytical method because the amino acids play different roles.

• Amino acids are the basic constituents of proteins. Qualitative and quantitative analysis of the amino acid composition of hydrolyzed samples of pure proteins or peptides is used to identify the material and to directly measure its concentration
• Amino acids are also intermediates in metabolic pathways, often not directly involving proteins. The amino acids are measured as elements of physiological and nutritional studies. This has proven particularly important in monitoring the growth of cells in cultures, as used in the production of biopharmaceuticals
• Similar considerations lead to the analysis of foods and feeds to ensure that nutritional requirements are met

With the UPLC^® Amino Acid Analysis Solution, you benefit from better resolution and sensitivity, all achieved in a shorter analysis time than with conventional methodologies:

• Method robustness minimizes variability
• Better resolution translates into accurate results
• UPLC delivers greater throughput than traditional HPLC
• Protein characterization accelerates for comparison of amino acid composition deduced from the gene sequence for a product or its natural counterpart
• Monitoring cell culture media for critical nutrients allows you to optimize expression efficiencies and to make timely product harvesting decisions
• Avoid costly reformulations primary nutritional components

Optimized Peak Identification

AccQ•Tag™ Ultra Chemistries used in the UPLC Amino Acid Analysis Solution are a comprehensive and fully-tested set of reagents, columns, and eluents optimized for use with the ACQUITY UPLC® System. With the system’s superior resolution of all amino acids, you will confidently achieve peak identification and quantitation, which in turn assures the accuracy of your results.

This chemistry is based on Waters’ widely-used and understood AccQ•Tag derivatizaton method. Primary and secondary amino acids react with a single reagent, AccQ•Fluor™, in a high-throughput batch process resulting in exceptionally stable derivatives. High resolution separations are achieved using pre-qualified AccQ•Tag Ultra UPLC columns and mobile phases. Derivatized amino acids are quantified to sub-picomole levels with single wavelength UV detection.

Performance Qualification

Qualification services available for the UPLC Amino Acid Analysis Solution meet the most stringent regulatory requirements. Installation, Operation, and Performance Qualification (IQ/OQ/PQ) protocols ensure that every element of the system is performing according to its intended use. An additional PQ, specific for amino acid analysis, is also available to verify performance and ensure accurate results.

Analysis of a Hydrolysate Standard at 10 pmol/mL

The UPLC Amino Acid Analysis Solution provides high resolution to ensure method robustness with good quantitation. The short cycle time is obtained without compromising accurate results.

Analysis of Hydrolysate and Cell Culture Standards

The upper trace shows the analysis of a hydrolysate standard at 10 pmol/mL, and the lower trace a standard mixture of the larger number of amino acids found in cell culture media, also at 10 pmol/mL. The adaptation of the method requires only a change in dilution of the Eluent A Concentrate supplied as part of the total system solution.

Efficient, Reliable Foods and Feed Sample Analysis: Soybean Meal Hydrolysate

Two samples of hydrolyzed soybean meal were analyzed. The upper trace shows the untreated sample while the lower trace shows the results of performic acid oxidation. Note the appearance of cysteic acid and methionine sulfone in the oxidized sample.

Direct Cell Culture Sample Analysis

Aliquots of cell culture media were taken directly from a bioreactor producing a biopharmaceutical protein. Samples were taken over a period of six days and no special sample preparation was required before the amino acid analysis shown here. The amino acid concentration trends can be plotted with growth as well as the response to feeding.