Tangential Flow Filtration Components

Membrane Cassettes

Ultrafiltration (UF) Membranes

Omega Membrane
Pall's Omega™ polyethersulfone (PES) membranes offer high flux- rates and selectivities. They have been specifically modified to minimize protein binding to the surface and interstitial structure of the membrane. This polymeric membrane is stable against biological and physical degradation due to the unique chemical properties of PES.

Omega membranes are cast on a highly porous, non-woven polyolefin support. They have an anisotropic structure, a thin skin-like top layer with a highly porous underlying support. The structure of the skin determines the porosity and permeability characteristics of the membrane and can typically be cleaned quicker and easier than membranes with a uniform, sub-micron depth structure.  This membrane is compatible with acids, bases and a variety of other cleaning agents to optimize for cleaning procedures.

Omega membranes are available in a wide range of nominal molecular weight cut-offs (MWCO) from 1 – 1,000 kDa.

Regenerated Cellulose Membrane
Regenerated cellulose membranes have hydrophilic surfaces and exhibit low protein binding characteristics. They typically clean up well with low concentrations of caustic solutions. While water fluxes are typically lower than PES membranes, the process flux can be more comparable.

Microfiltration (MF) Membranes

Supor® TFF Membrane
Supor TFF membrane is a polyethersulfone membrane with a uniform depth structure. The membrane porosity is optimized for microfiltration TFF applications including harvest, concentration and clarification of cell cultures and fermentation broths. It is currentlly available in 0.1, 0.2, 0.45, 0.65 micron pore size membranes. Use Supor TFF membranes to harvest bacterial, mammalian, and insect cells; separate red blood cells from hemoglobin; and clarify yeast broth and bacterial lysates.
 

















TFF Cassettes

Minimate™ Tangential Flow Filtration Capsules
The easy-to-use Minimate TFF capsule is a valuable tool for any laboratory requiring tangential flow filtration of small process volumes. This versatile, 'plug-and-play', self-contained device (no holder required) is designed to operate with the Minimate™ TFF System or Minim™ II Tangential Flow Filtration System. It comes supplied with fittings and tubing to simplify installation into most small filtration setups. Sample batch sizes of up to one liter can be reduced to as low as 5 mL quickly and with little user intervention. Sample concentration and diafiltration (desalting) can take place sequentially using the same device and system, saving time and avoiding product loss associated with transfer steps. Minimate TFF capsules contain Pall's proprietary Omega™ low non-specific adsorption UF membrane, available in a wide range of molecular weight cut-offs for improved  product recovery. Minimate TFF capsules can be used in a variety of TFF applications in biotechnology, molecular biology, protein chemistry, microbiology and immunology.

Omega™ T-Series Membrane Cassettes
T-Series membrane cassettes represent one of Pall’s latest advances in tangential flow filtration technology. These cassettes incorporate Pall’s proprietary Omega membrane with improvements in materials and design to optimize separation efficiency. Omega T-Series cassettes are available in our successful and long-established Centramate™ and Centrasette™ screen channel formats.

Omega™ C & F Series Cassettes
The long-established C & F Series TFF cassettes incorporate Omega UF membrane or Supor TFF MF membranes. These cassettes are available with Centramate, Centrasette, Maximate™ or Maxisette™ membranes, in both screen and suspended screen formats.

Centramate™ Tangential Flow Filtration Membrane Cassettes
Centramate™ TFF cassettes are perfect for laboratory-scale and development applications in TFF. Small area format (0.019 m2) can be used with Centramate™ LV Tangential Flow Filtration Membrane Cassette holders to process volumes of a few milliliters to several liters.

The larger, 0.1 m2 area cassettes fit in various Centramate holders where up to five cassettes can be stacked to process volumes from < 1 L to > 50 L. Applications developed on a Centramate cassette can be easily scaled up by stacking cassettes in a Centramate holder or by switching to the Centrasette cassette format with identical membrane, path length and channel format.

Centrasette™ Tangential Flow Filtration Membrane Cassettes
Centrasette TFF cassettes are available in the same range of membrane and screen formats as Centramate cassettes, but with a larger footprint and membrane area. These are ideal for pilot-scale or production-scale work in various tangential flow filtration applications, including concentration and diafiltration by the biopharmaceutical industry. These cassettes are available in several formats with membrane area of 0.5 m2 and 2.5 m2. Cassettes may be stacked in holders to build systems with membrane areas > 80 m2.

Maximate™ Tangential Flow Filtration Membrane Cassettes
Maximate TFF cassettes are available in the same membranes and screen and suspended screen formats as the Centramate/Centrasette cassettes. They offer the opportunity to simulate the performance of the larger Maxisette cassette on a smaller scale. Maximate cassettes have distinct benefits that make them advantageous as a development tool for larger-volume TFF processes.

Maxisette™ Tangential Flow Filtration Membrane Cassettes
Maxisette TFF cassettes offer the same benefits as the Maximate cassette for much larger volume processes.  The volumetric flow rate required is 40% lower compared to Centrasette cassettes.  The larger porting (almost 50% bigger) in the Maxisette provides lower resistance to high feed low rates which results in lower pressure drops and easier cleaning. The cassettes are offered in both screen and suspended screen formats with Omega UF or Supor TFF MF membranes.

Tangential Flow Filtration Membrane Cassette Holders

Designed for optimum performance and product recovery, Pall® TFF holders are available in a variety of sizes to meet every application requirement.

Centramate™ LV Tangential Flow Filtration Membrane Cassette Holder
The stainless steel Centramate LV holder can accommodate up to two Centramate 0.019 m2 cassettes.  The holder can be incorporated in to a system consisting of a reservoir, pump and range of accessories such as tubing, valves, fittings, and pressure gauges. It is typically used with the Minim™ II Tangential Flow Filtration System and can also be incorporated into a Minimate™ TFF System.

Centramate PE Tangential Flow Filtration Membrane Cassette Holder
The Centramate PE holder has a polyethylene manifold with ¼ in. NPT-threaded ports sandwiched between 304 stainless steel outer plates. It is recommended for use in applications where metal contact must be avoided. The Centramate PE holder is ideal for applications in which 0.1 m2 cassettes are used as single-use components so that cleaning and cleaning validation can be eliminated. It can accommodate up to four screen channel cassettes. The holder is available with either two or three pressure gauge fitting kits. The addition of a pump and reservoir (Ultralab System) completes the system.

Centramate Stainless Steel (SS) Tangential Flow Filtration Membrane Cassette Holder
The Centramate stainless steel cassette holder (316L) comes with ½ in. sanitary flanges on feed and permeate ports. Up to five 0.1 m2 screen channel cassettes can be accommodated. The holder is available with either two or three pressure gauge fitting kits. The addition of a pump and reservoir (Ultralab System) completes the system. A Centramate SS Holder is also incorporated into the Centramate™ 500 S benchtop Tangential Flow Filtration System.

Centrasette™ LV Stainless Steel Tangential Flow Filtration Membrane Cassette Holder
The Centrasette 5 holders are manufactured using highly-polished 316L stainless steel. They are ideal for use in pilot and process-scale applications where membrane areas from 0.5 m2 to 2.5 m2 can be installed. The holder incorporates ¾ inch sanitary flanges on the feed, retentate and permeate ports for easy connection into a sanitary system and to minimize system hold-up volume.

Centrasette™ 5 Stainless Steel Tangential Flow Filtration Membrane Cassette Holder
The Centrasette 5 holders are manufactured using highly-polished 316L stainless steel. They are ideal for use in pilot and process-scale applications where membrane areas from 0.5 m2 to 5 m2 can be installed per holder. The holders are also available in auto-torque format with hydraulic system including stainless steel pistons and pump to maintain optimal and uniform compression on the installed cassettes.  Both two and three pressure gauge fitting kits are available.

Centrasette™ P Tangential Flow Filtration Membrane Cassette Holder
The Centrasette P holder has a polypropylene manifold and end plate. These holders are designed for product metal contact is not desirable or prohibited by your application.  The manifold and end plates are housed between stainless steel plates to supply the necessary rigidity when operating at high pressures.  Luer fittings on the ¾ inch sanitary polypropylene ports can be used for connecting to plastic pressure transducers.  The economical plastic manifold and end plate can be used as single-use components so that cleaning or cleaning validation can be eliminated. This can also help prevent sample cross contamination. 

Maximate™ Stainless Steel Tangential Flow Filtration Membrane Cassette Holders
The Maximate holder is manufactured using highly-polished 316L stainless steel.  It is ideal for use in development and pilot-scale applications, especially those that may scale into a system incorporating the Maxisette format. Up to six 0.18 m2 screen channel cassettes can be accommodated. The holder incorporates ¾ inch sanitary flanges on the feed, and retentate ports and ½ inch flanges on the permeate ports for easy connection into a sanitary system and to minimize system hold-up volume. Sanitary fitting kits with either two or three pressure gauges are available for system assembling. The addition of a pump and reservoir completes the system.

Maxisette™ Stainless Steel Tangential Flow Filtration Membrane Cassette Holders
Maxisette holders are designed for optimal performance in a large-scale production environment. All the wetted surfaces are electropolished 316 L stainless steel. The smaller footprint makes it ideal for use in process skids and manufacturing suites. The feed flow direction is from bottom to top, allowing air to be easily expelled from the system.  The holders are available in auto-torque format with hydraulic system for minimal and uniform compression on the installed cassettes.

Fitting Packages and Components

Complete fittings kits consisting of filtrate manifold, pressure gauges, valves, hose connectors, gaskets and clamps are available for most cassette holders. Ordering a complete fitting kit with the cassette holder simplifies installation into a system and avoids potential delays in starting your process due to missing components.

Hollow Fibers

Pall’s Microza polymeric hollow fiber membranes are made from durable fibers available in a wide variety of ratings, polymers and sizes. Applications are as diverse as cell broth clarification, long-term sterility maintenance in critical mammalian cell culture perfusion, concentration and purification of bulk enzyme solutions, filtration of solutions of buffers and active ingredients to remove endotoxin and concentration and diafiltration of recombinant protein solutions.

Available ratings span the range from low molecular-weight ultrafiltration through to microfiltration. All Microza membranes are supplied as self-contained modules, with no additional requirement for housings, enabling simplicity of system design. Modules are available that can be autoclaved, and many can be steamed, facilitating aseptic operation through the use of Steam-In-Place (SIP). Microza membranes have surfaces that minimize entrapment and facilitate cleaning.

All Microza membranes are manufactured in a single step, and are not composed of laminates. Membranes and modules are subjected to rigorous quality control to ensure consistency of performance, durability in service and module integrity for the most demanding applications.

Ultrafiltration Hollow Fiber Modules

Microza ultrafiltration modules comprise a unique, double-skinned proprietary membrane surface over a dense, highly porous internal layer support for excellent flow characteristics, and outstanding fiber durability in long-term service. Microza UF membranes are resistant to flow in both directions, so there is no risk of delamination or membrane rupture if back-pressure is applied. In fact, in many installations, backpulsing can be used to maintain flux during extended run times.

The SP and VIP modules have polysulfone (PS) membrane and are available in 4 kDa, 6 kDa and 10 kDa molecular weight cut-offs and in a range of sizes from 170 cm2 (0.18 ft2) to more than 5 m2 (54 ft2). They meet the specification for biological tests listed in the current revision of USP for class VI plastics at 121ºC (250 ºF). The modules can be autoclaved, steamed or chemically sanitized for used in a range of pharmaceutical applications. Production size modules may be hot water sanitized up to 95 ºC (203 ºF). Polysulfone membranes exhibit excellent resistance to pressure, temperature and aggressive cleaning regimes. They are compatible with a wide range of cleaning agents such as 5000 ppm sodium hypochlorite or 4% sodium hydroxide. PS membranes have very low affinity and adsorption characteristics resulting in high product recoveries, and long module service life.

The AP and AV series ultrafiltration modules feature polyacrylonitrile (PAN) membranes. They are available in 6 kDa and 13 kDa molecular weight cut-offs and in a range of sizes from 170 cm2 (0.18 ft2) to more than 12 m2 (130 ft2). They are rated for continuous operation up to 50 ºC (122 ºF) and meet the specifications for biological tests listed in the current revision of USP for Class VI plastics at 121 ºC (250 ºF). PAN membranes are ideally suited to bulk-process applications, such as the purification of enzymes. They exhibit high-strength, coupled with high flux rates, minimizing installation size. PAN has a low fouling characteristic for these applications, simplifying cleaning.

Microfiltration Hollow Fiber Modules

Microza micofiltration membranes have smooth inner and outer membrane skins with a highly porous symmetrical support structure, giving high-flow rates. These modules can also be backflushed.

The UJP and UMP series of Microza hollow fiber microfiltration modules feature a unique, proprietary, low protein-binding membrane of a specially resilient polyvinylidenedi fluoride (PVDF). They are available in 0.2 μm and 0.65 micron fiber ratings and sizes ranging from 0.02 m2 (0.21 ft2) to 4.0 m2 (43 ft2) for process scaling from laboratory to production. Inner-diameter of fibers, at 1.1 mm and 1.4 mm, reduce the possibility of cells accumulating and plugging the fibers. The modules may be sterilized by Steam-In-Place (SIP) or autoclaved. Microza HF modules meet specifications for biological tests listed in the current revision of USP for Class VI plastics at 121°C.

For clarification, concentration or use as part of a perfusion system, the Microza MF modules are designed to meet the pharmaceutical requirements for product recovery from cell culture/fermentation broths of bacterial, mammalian, insect and other cells. Microza MF modules are easily cleaned and reusable, making them a cost-effective process tool. 

Vibrating Membrane Filters (VMF)

PallSep™ Vibrating Membrane Filtration Technology is an enabling technology for difficult processes where the security of a polymeric barrier process is required, but where feed materials are very high in complex mixtures of biomolecules and viscosities may be elevated. PallSep filtration units represent a significant innovation in membrane filtration. In all membrane processes, shear forces are generated above the membrane surface to counteract the effects of membrane fouling. With PallSep technology, shear is generated by horizontal vibration of the membrane elements through the feed fluid over fifty times per second. The shear, which is higher than that typically generated in conventional tangential flow filtration (TFF), is limited to a small boundary layer above the membrane surface and not applied to the bulk of the fluid. This means that fluids may be processed in a very gentle manner, through an open flow path with minimal pressure-drop (even transmembrane pressure distribution) to high suspended solids levels (>60% w/v)*. The Biotech PallSep PS 50 device consists of an encapsulated stack of 0.2 micron polyethersulfone (PES) membrane elements (0.2, 1 or 5 m2 membrane area), which are mounted on a torsion bar. Kinetic energy from a small motor is efficiently converted to vibrational energy in the stack whose oscillation is controlled by a frequency converter. The Biotech PallSep device is typically used for process-development work with fluid volumes between 2 and 100 L.

The principal applications for the Biotech VMF system involve characterization of cell homogenates and extracts from plants and animals sources that are difficult to process by either conventional TFF or centrifugation. Examples are direct processing of mycelial fermentation broths without pretreatment and recovery of cell wall fractions from chemically-lysed recombinant bacterial systems used to produce therapeutic vaccines.