Support for SFC Method Development : Method Scouting Systems

For typical HPLC or SFC analysis, scouting (searching) for optimal separation parameters requires a time-consuming analytical condition optimization process of manually adjusting solutions, replacing columns, and specifying gradient profile settings. In particular, because predicting the retention mode for SFC is more difficult than for regular HPLC, separation parameter scouting must be performed comprehensively.
The separation parameter optimization stage requires a process of checking retention behavior as the type and concentration of solvents and additives are varied. Due to the time and trouble involved in the modifier preparation process, it often results in discarding a greater quantity of unwanted solution.
The Nexera UC/s system includes an internal valve for automatically switching between columns and mobile phases/modifiers and includes functionality for automatically blending mobile phases to vary the types of solvents, and the types and concentrations of additives used. By using the valve to switch between columns with multiple separation modes, it can comprehensively scout separation parameters. Fig. 1 shows the mobile phase blending process used to automatically prepare modifiers.

Fig.1 Flow Diagram of Mobile Phase Blending Process

Using dedicated Method Scouting Solution software, separation parameters can be scouted comprehensively for multiple analytical conditions (Fig. 2). Based on the chromatogram obtained, optional software is used to evaluate separation and rank the optimized parameters (Fig. 3). The software automatically identifies all chromatograms with resolution greater than a specified criterion (1.5 in this case) and then ranks the resolution in those chromatograms.