Diversification of Separation Selectivity Using Supercritical Fluid Chromatography -Efficient Search for Optimal Separation Conditions by Combining LC and SFC-

User Benefits

- Because LC and SFC have different separation characteristics, SFC has the potential to separate compounds that are difficult to resolve by LC. - Both LC and SFC analyses can be performed on a single system. - By utilizing mobile phase and column switching valves, LabSolutions MD enables automated screening of mobile phases and columns.

Introduction

Supercritical Fluid Chromatography (SFC) is a separation technique that employs supercritical carbon dioxide as the primary mobile phase. Owing to its high diffusion coefficient and low viscosity, supercritical carbon dioxide allows high flow-rate delivery at lower column backpressure compared to Liquid Chromatography (LC), enabling shorter analysis time. It also provides excellent separation performance for structurally related compounds. However, since supercritical carbon dioxide has a polarity similar to that of hexane, it often lacks sufficient elution strength on its own. Therefore, organic solvents (modifiers) such as methanol, acetonitrile, 2-propanol, and ethanol are commonly added to the mobile phase to adjust polarity. By appropriately selecting and combining these modifiers, the interaction between analytes and the stationary phase can be finely tuned, resulting in diverse separation patterns. Because SFC and LC exhibit different retention behaviors, compounds that are difficult to separate by LC may be effectively separated by SFC. Accordingly, combining both techniques in method development can improve the efficiency of searching for optimal separation conditions. On the other hand, both column and mobile phase selection have a strong influence on retention behavior. To obtain optimal separation, it is ideal to examine multiple types of columns and mobile phases. However, this process is highly labor- and time-intensive. This study demonstrates efficient optimization of separation conditions using Nexera UC/s (LC/SFC switching system), which allows LC and SFC analyses to be performed on a single instrument, in combination with the LabSolutions MD, a dedicated software for supporting method development. Column and mobile phase screening were conducted using a mixed sample containing six small-molecule pharmaceutical compounds as a model sample.

November 11, 2025 GMT