Integration of Rapid Derivatization and Gradient Elution Techniques for Enhanced High-Performance Liquid Chromatography Analysis of Key Amino Acids in Wheat Flour

A rapid pre-column derivatization process before ultraviolet chromatographic analysis using a Pico-Tag C-18 column was developed in combination with modified gradient elution techniques for the analysis of key amino acids (proline and glutamine) in wheat flour. With use of a vacuum concentrator at 45degreesC, the pre-column derivatization process was significantly accelerated before entering a reverse-phase high-performance liquid chromatography. When running at an optimized scheme-in which the gradient elution started at a flow rate of I mL/ min and then gradually increased to 1.3 mL/min in 22 min, followed by reset to 1 mL/min at 45 min-the profiled mobile phase mixture was able to yield chromatograms with desirable retention factor and resolution.