High Performance Liquid Chromatographic Analyses of Sulphonamides and Dihydrofolate Reductase Inhibitors. II. Separations in Acetonitrile Modified Solutions, Ternary Gradient Studies & Flow Programming

Theory of Stepwise Gradient Elution in Reversed-Phase Liquid Chromatography Coupled with Flow Rate Variations: Application to Retention Prediction and Separation Optimization of a Set of Amino Acids

“…Although solvent programming is probably the best single gradient method in LC to control the separation where fast and highly efficient analysis is desirable, it can sometimes suffer from poor front-end resolution. , Thus, the coupling of solvent and flow programming, that is, a “dual-mode gradient”, can become a powerful tool for altering separation quality in many situations. However, there are only a few reports concerning such reversed-phase, dual-mode gradient elution in the literature, − since it seems that the development of this separation method is more difficult than that of a single-gradient elution mode.…”