Many research applications require concentration of dilute protein solutions. Protein solutions may be concentrated by precipitation, chromatographic capture and elution, or by lyophilization. A disadvantage of lyophilization is non-protein agents are concentrated along with the protein and these may interfere with subsequent downstream applications. G-Biosciences offers a selection of protein concentration kits suitable for concentrating proteins for running gels, raising antibodies, protein purification, protein assays and other applications. Proteins concentrated with these kits are suitable for the majority of downstream applications.