Persefose 6B is a modified highly cross-linked (cross-linking ratio is 6%) agarose-based gel filtration chromatography medium, which separates different molecules by using their molecular weight and conformation differences. This chromatography medium can be used successfully for the separation and purification of various biological molecules such as recombinant proteins, antibodies, nucleic acids, viruses and virus-like particles, and polysaccharides, as well as QC molecular weight determination. It is especially suitable for molecules that cannot be dissolved in aqueous solution.