Influence of the organic modifier and the ion-pairing agent in the mobile phase on the separation of soya bean proteins by perfusion liquid chromatography. Analysis of commercial dairylike soya bean products using multivariate techniques

摘要

The influence of the nature and concentration of the organic modifier and the ion-pairing agent in the mobile phase on the separation of soya bean proteins by perfusion reversed-phase high-performance liquid chromatography was investigated. Acetonitrile, methanol, and isopropanol were used as organic modifiers, and trifluoroacetic acid (TFA), heptafluorobutyric acid (HFBA), morpholine (MP), and mixtures thereof as ion-pairing agents. Different linear binary gradients were tried and the best separation) were obtained when using isopropanol and acetonitrille as organic modifiers and mixtures of TFA and MP as ion-pairing agents. Two elution gradients were chosen in order to achieve the characterisation of dairylike soya bean products on the basis of their chromatographic profiles by multivariate techniques: an isopropanol-water gradient, 0.1% (v/v) TFA-0.2% (v/v) MP in both phases, 3-20% B in 3.5 min and 20-45% B in 1.5 min (flow rate, 3 mL/min), and an acetonitrile-water gradient, 0.1% (v/v) TFA-0.1% (v/v) MP in both phases, 5-25% B in 1.75 min and 25-45% B in 1.75 min (flow rate, 4mL/min). Finally, the isopropanol-water gradient was also applied to the analysis of soya bean proteins in commercial dairylike soya bean products by using multivariate techniques.