Using reaction flow chromatography for the analysis of amino acid: Derivatisation with fluorescamine reagent

• Reaction flow chromatography columns were used for amino acid analysis with post column derivatisation.
• The derivatisation process using RF was more efficient than conventional HPLC.
• Better sensitivity was obtained using RF columns compared to conventional HPLC columns.

Reaction flow (RF) chromatography with fluorescamine reagent and UV–vis detection was used for the analysis of amino acids. The performance advantage of RF chromatography was tested against the conventional post-column derivatisation (PCD) methods. The results of the study verified that greater sensitivity could be obtained using RF columns compared to conventional PCD methods. The reaction loops employed in the conventional PCD methods did not need to be used, which resulted in more efficient separations using RF columns. The selective detection of amino acids in this RF study reduced limits of detection (LOD) and limits of quantification (LOQ) by about 50% compared to conventional methods of PCD. The calibration data of the RF-PCD technique also yielded R2 ≥ 0.99 and %RSD in peak areas ranging from 3.0–8.5%. The RF method also enabled multiplexed detection since both the derivatised and non-derivatised flow streams could be analysed simultaneously.