Analytical wide pore HPLC columns for the determination of larger biomolecules
Find silica gel based columns for the analysis of larger molecules (>2000 Da) like proteins and peptides. To separate these larger molecules, they need to freely access the interior of the pores of the packing material. Therefore, the analytes’ diameter must be smaller than the average pore diameter. For higher molecular weight solutes, the use of lower pore size materials (60-120 Å) as typically used for the analysis of small molecules may result restricted diffusion in the material´s pores and therewith reduced column efficiency.
The use of larger pore silica-based bonded phases leads to improvements in resolution, capacity and recovery of proteins and other biomolecules, due to a reduction in size exclusion mechanism and enhanced molecular diffusion rates. A pore size of 300 Å has become the accepted standard for wide pore silica gels because it has been found to be suitable for a broad range of molecular weight proteins, peptides and oligonucleotides. In general, peptides exceeding approximately 50 amino acids and oligonucleotides greater than 25 residues are preferentially analyzed on 300 Å materials.
Separations of very large biomolecules (MW >100,000Da) may require larger pore size packings (500 to 4000 Å).