How to improve your implementation of two-dimensional preparative HPLC : solvent viscosity considerations

The biologics and natural product industries rely heavily on separation technology. Sample analyses are undertaken on the analytical scale, and isolation and purification are undertaken at the preparative scale. Key target components are often isolated to provide standard reference materials for future product quality assurance testing. These products are often very complex mixtures, requiring separation systems to have a high peak capacity for both analytical and preparative scale separations. A technique gaining popularity among companies that require the isolation of pure compounds from complex sample matrices is two-dimensional liquid chromatography, which can be conducted at either the analytical (2D-HPLC) or preparative scale (2D-PHPLC). Operated in a heart-cutting mode, 2D-PHPLC is a technique for which the first dimension essentially serves as an extraction step, simplifying the sample matrix before separation of target analyte(s) in the second dimension. In the comprehensive mode (LC × LC), it is useful for analytical analysis and sample profiling.