Downstream analyses require that proteins, nucleic acids, virus particles, and other biomolecules are solubilized in their native form at an appropriate concentration. Ultrafiltration methods can be used to gently and efficiently concentrate biological or environmental samples by removing excess liquid or buffer. A variety of ultrafiltration devices are available to rapidly concentrate proteins and other biomolecules with high recovery.
Centrifugal ultrafiltration devices use centrifugal force to gently drive solutes and liquids through a semi-permeable membrane for quick concentration of proteins, antibodies, and other biomolecules in small to medium volume samples.
Simply and efficiently concentrate and desalt solutions of peptides, proteins, and genomic DNA with low-binding Ultracel® regenerated cellulose (RC) or Biomax® PES membranes using any centrifuge that can accept 1.5 mL tubes.
Ultrafree®-MC and Ultrafree®-CL centrifugal filters remove particles and precipitates from aqueous and some solvent-based samples. These fast filtration units provide highly reproducible performance for sample recovery.
Amicon® Ultra Centrifugal filters provide fast sample processing and promote high sample recoveries, even in dilute samples, through ultrafiltration. The unique features of the Amicon® Ultra centrifugal filters give you the fastest, most efficient concentration for sensitive downstream applications.
The Centricon® Plus-70 centrifugal filter is designed for rapid processing of aqueous biological solutions in volumes ranging from 15 to 70 mL. Centricon® filters concentrate most 70 mL solutions down to 350 μL in as little as 25 minutes. Samples are typically concentrated in the 50X to 200X range, depending on the sample type and starting sample volume. These units are a convenient alternative to dialysis, lyophilization, or precipitation techniques.
Stirred cells use pressurized ultrafiltration (pUF) at high flow rates to process large sample volumes for rapid concentration of proteins, virus particles, and other biological and environmental samples.
Amicon® stirred cells provide high flow rates with solutions up to 10% macrosolute concentration and are capable of rapid concentration or salt removal followed by concentration in the same unit. For protein concentration, gas pressure is applied directly to ultrafiltration cell. Solutes above the membrane’s nominal molecular weight cut-off (NMWCO) are retained in cell, while water and solutes below the cut-off pass into the filtrate and out of cell.
The Millipore® Solvent Resistant Stirred Cell is constructed from stainless steel and borosilicate glass for applications requiring compatibility with solvents. It is designed to offer a rapid and efficient method for concentrating or desalting samples of up to 300 mL under high pressure.
The Centrifree® filter was designed with the clinical laboratory in mind. These devices rapidly and efficiently separate free from protein-bound microsolute in small volumes (0.15–1.0 mL) of serum, plasma, and other biological samples using ultrafiltration. Accurate partitioning occurs in minutes without dilution, change in physiologic pH, ion composition, or unbound microsolute concentration. These devices contain low-adsorptive hydrophilic membranes and O-rings without plasticizers to ensure excellent recovery.
Minicon® concentrators are non-sterile, disposable, multiwell ultrafiltration devices designed for concentrating macromolecules in clinical specimens such as urine, cerebrospinal fluid (CSF) or other biological solutions. The concentrators, which require no additional equipment and can be operated unattended, are used by researchers and clinical laboratories worldwide as a preparatory step to increase the sensitivity of subsequent tests.