Claudio Brunelli

Supercritical fluid chromatography (SFC) is a well-established analytical technique used in the pharmaceutical industry for decades. However, it is still considered a new technique in some areas, for example, implementing the technique for purity profiling in late-stage development and production. In pharmaceutical analytical departments, SFC serves a wide variety of purposes, including compound purification, purity profile, and chiral analysis. Depending on the phase of drug development, the analytical performance requirements, such as speed of analysis, efficiency, and sensitivity, may vary considerably. The end goal is to provide robust, reliable and transferable analytical SFC methods. The challenges for future development and widespread implementation of SFC and the implementation of SFC in quality control (QC) laboratories using modern instrumentation are also discussed.

On-line two-dimensional liquid chromatography (2D-LC) embracing mainly comprehensive LC (LC×LC) and multiple heart-cutting LC (mLC–LC) offers new opportunities for in-depth characterization of pharmaceuticals. Reversed-phase LC × reversed-phase LC using different column chemistries and mobile phases provides good orthogonality for a wide range of applications related to small molecule drugs. Moreover, hardware configurations and software are now commercially available to perform LC×LC and mLC–LC measurements in a reproducible manner.

A simple experimental setup applied in a drug discovery laboratory illustrates some anomalies and misconceptions about supercritical fluid chromatography for drug discovery.

The second part of this series on green chromatography describes characteristics of GC and SFC