QuikPrep® SpinColumns™ for gel filtration chromatography can be used for protein purification, buffer exchange, desalting, or for group separation. Gel filtration, also called size-exclusion chromatography is an easy-to-use method for separation of molecules with different molecular sizes, using mild conditions. Gel filtration uses the size of molecules in solution to determine separation. SpinColumns™ have short media packing so the samples are separated by size, the large molecules travel out of the column with the void volume the smaller molecules, salts, etc. remain in the column. Desalting columns are used not only to remove low molecular weight contaminants such as salt, but also for buffer exchange before and after different chromatography techniques and for the rapid removal of reagents to terminate a reaction.

Examples of group separations include:

• Removal of unincorporated nucleotides during DNA sequencing
• Removal of free low molecular weight labels
• Termination of reactions between macromolecules and low molecular weight reactants
• Removal of products, cofactors or inhibitors from enzymes
• Removal of unreacted radiolabels such as [α-32P]-ATP from nucleic acid labeling reactions
• G-10, G-25, G-50- G-100 = Sephadex
• P-2, P-6, P-30 = Porous polyacrylamide beads