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Laboratory Dialysis & Diafiltration Devices

Each protein preparation is unique. Give your prep the special treatment it deserves with a perfectly engineered device for dialysis or diafiltration. Our tools were designed to gently process samples while preventing precipitation or over-concentration. Find the ideal product from our selection of dialyzers and diafiltration devices that quickly and efficiently desalt, buffer exchange, and remove contaminants and impurities from protein and other biomolecular samples.

Dialyzers rely on passive diffusion for buffer exchange and desalting through placement of the dialyzer in a bath or reservoir filled with exchange buffer. Diafiltration is a technique that uses ultrafiltration for buffer exchange, eliminating salts and microsolutes in a process called “washing out”.

In both processes, separation is achieved by selective diffusion across a porous, semi-permeable membrane that allows permeation of small molecules including solvents, salts, and small metabolites while blocking the passage of larger molecules, such as proteins.

  • Dialyzers are recommended for small to medium scale dialysis (10 µL - 15 mL sample volumes).
  • Centrifugal ultrafiltration devices use centrifugal pressure to gently drive solutes through the membrane for diafiltration of biological samples ranging from 0.5 mL - 15 mL.
  • For larger samples volumes, stirred cells can be used for continuous diafiltration of biological and environmental samples up to 400 mL, with an optional external 800 mL reservoir for expanded capacity.


Dialyzers

Gently and easily dialyze protein or nucleic acid samples using D-Tube™ dialyzers. These devices feature dialysis membrane windows in a capped centrifuge tube format, enabling efficient buffer exchange to remove urea, detergents, salt, and other microsolutes. Designed with a double membrane, D-Tube™ dialyzers spread the sample over a large area so that dialysis is complete in 2-5 hours.

  • Easy-to-handle dialyzers for buffer exchange and removal of urea and detergents
  • Offered in several sizes including Mini (10-250 µL), Midi (50-800 µL), Maxi (100 µL - 3 mL), and Mega (10, 15, or 20 mL)
  • Leak-resistant design — no clamps or knots required
  • No syringe required to load or withdraw samples. Simply load your sample with standard pipette tip.
  • Screw cap for easy opening and closing
  • High sample volume recovery (>90%)

Amicon® Centrifugal Ultrafiltration Devices

Amicon® Ultra centrifugal filters enable rapid desalting, buffer exchange, and diafiltration of 0.5 mL -15 mL sample volumes with high sample recovery. Amicon® Ultra centrifugal devices use Ultracel® regenerated cellulose (RC) membranes for gentle ultrafiltration and are offered with nominal molecular weight limits (NMWLs) of 3 kDa, 10 kDa, 30 kDa, 50 kDa, and 100 kDa.

  • Small- and mid-volume ultrafiltration for 0.1 mL - 15 mL sample volumes
  • Low binding membrane and polypropylene housing for >90% sample recovery
  • Ultra-fast sample processing in as little as 10 minutes
  • Compatible with a variety of organic solvents and aqueous solutions, pH 1 to 9

Stirred Cells

Stirred cells use pressurized ultrafiltration (pUF) at high flow rates to process large sample volumes for rapid diafiltration and buffer exchange. Gas pressure is applied directly to the cell for filtration.

Amicon® Stirred Cells:

  • Offered in three different sizes to handle volumes from 50 mL to 400 mL, with an optional external 800 mL reservoir for expanded capacity
  • Gentle sample processing using magnetic stirring to minimize polarization and shear denaturation
  • High flow rates for rapid diafiltration
  • Reusable and autoclavable for sterility

Solvent-resistant stirred cells:

  • Designed for applications requiring compatibility with solvents
  • Borosilicate glass cylinder and PTFE components for broad compatibility
  • Autoclavable with membrane in-place
  • Top plate opening provides access to contents without dismantling
  • Few components for easier cleaning and assembly

Disc membranes for stirred cells

Disc membranes are designed for use with stirred cells for buffer exchange, desalting, and diafiltration. Ultrafiltration disc membranes are available in Ultracel® regenerated cellulose and Biomax® polyethersulvone (PES). These membranes are available in a range of different pore sizes and diameters.

  • Ultracel® regenerated cellulose ultrafiltration membranes are recommended for concentrating or desalting dilute solutions. The hydrophilic, tight microstructure of Ultracel® membranes assures the highest possible retention with the lowest possible adsorption of protein, DNA or other macromolecules.
  • Biomax® PES ultrafiltration membranes are recommended for concentrating or desalting higher volumes of more concentrated samples such as serum, plasma, or conditioned tissue culture media.



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