Analysis of Amino Acids by Automated Pre-column Derivatization with OPA

Pre-column derivatization methods for amino acid analysis have been widely used in reversed-phase HPLC, as they offer high selectivity and sensitivity for multiple components. Many derivatization reagents are commercially available and one can choose the most suitable reagent for the application. Among them, orthophtalaldehyde (OPA) is one of the most commonly used reagents because it reacts with amino acids very quickly (seconds) at room temperature and derivatized amino acids can be detected by a fluorescence detector offering increased sensitivity. In this application, the OPA pre-column derivatization is demonstrated by using the automated pre-column derivatization function of JASCO’s autosampler for much better reproducibility than manual sampling.