Size-exclusion chromatography using core-shell particles

•Core-shell particles can be used successfully in size-exclusion chromatography.•Resolution is at least comparable with conventional SEC systems.•Analysis times in SEC can be reduced tenfold by using small (sub-2-μm) particles.•Very fast SEC separations are needed for comprehensive two-dimensional liquid chromatography.

Size-exclusion chromatography (SEC) is an indispensable technique for the separation of high-molecular-weight analytes and for determining molar-mass distributions. The potential application of SEC as second-dimension separation in comprehensive two-dimensional liquid chromatography demands very short analysis times. Liquid chromatography benefits from the advent of highly efficient core-shell packing materials, but because of the reduced total pore volume these materials have so far not been explored in SEC.The feasibility of using core-shell particles in SEC has been investigated and contemporary core-shell materials were compared with conventional packing materials for SEC. Columns packed with very small core-shell particles showed excellent resolution in specific molar-mass ranges, depending on the pore size. The analysis times were about an order of magnitude shorter than what could be achieved using conventional SEC columns.