Filters and Supporting Hardware The path to new discoveries must be laid on a solid foundation. Backed by decades of research, our exhaustive portfolio of fundamental filters and supporting hardware has helped generations of scientists reach new milestones. With the needs of today’s scientist at the top of our minds, we have continued to evolve, ensuring our products can continue to serve as the cornerstone for your latest innovation. The life science business of Merck operates as MilliporeSigma in the U.S. and Canada.

1.1 Membrane Filter and Filter Paper Prefiltration and Depth Filters 3 1.2 Filter Types by Characteristics 4 Glass and Quartz Fiber Filters 5 1.3 Filter Types by Application 6 Glass and Quartz Fiber Filters 8 1.4 Filter Product Tables 12 Polyvinylidene Fluoride (PVDF) 18 Aluminum Oxide (alumina) 27 Glass and Quartz Fiber Filters 28 1.5 Supporting Hardware, Vacuum Pumps, and

1.1 Membrane Filter and Filter Paper Characteristics Selecting the ideal filter begins with understanding their basic characteristics. Matching characteristics to sample properties and the desired filtration outcome can provide guidance on the utility of a given membrane filter or filter paper in your application. While the terms membrane filter and filter paper are often used interchangeably, these distinct filter types have unique properties, advantages, and disadvantages. Membrane Filters Produced by the precipitation or stretching of polymeric materials, membrane filters are one of the most...

Membrane filter properties differ markedly based upon their composition, fabrication method, surface treatment, and pore size. The table below organizes membrane filters by composition, providing general characteristics for each membrane type. Product groups belonging to each membrane type can be found in the last row of each column. Polyvinylidene Fluoride (PVDF) Chemical Compatibility Pore Size Flow Rate Protein Binding Optical Properties Hydrophilic or Hydrophobic 0.1 - 5 pm Slow to Medium Hydrophobic: High • Plain surface Medium Hydrophilic 0.025 - 8 pm Medium Medium Medium to Low Hydrophilic...

Membrane Filters (continued) tPurity reported as nominal ash content, as determined by ignition of the filter at 900 °C in air

The tables below provide product recommendations for research, industrial, and analytical applications, based upon general physical characteristics of each product group. While this chart provides general recommendations, filter compatibility with the sample and filtration method should be verified prior to use. +This application only applies to specific membrane filters within the product group. Please see specific application details for the product of interest on www.sigmaaldrich.com

+This application only applies to specific membrane filters within the product group. Please see specific application details for the product of interest on www.sigmaaldrich.com

8 Filters and Supporting Hardware

Whatman® filter paper

Whatman® filter paper Filters and Supporting Hardware

Whatman® filter paper

The product tables below have grouped our comprehensive filtration offering by material, providing more specific application recommendations, specific product characteristics, and dimensions. While these charts provide recommendations, filter compatibility with the sample and filtration method should be verified prior to use. CelluloseMillipore® Filtration ProductsMF-Millipore™ Membrane Filters Produced from biologically inert cellulose acetate and cellulose nitrate, MF-Millipore™ mixed cellulose ester membranes are a versatile choice for biological, analytical, environmental monitoring, and...

MF-Millipore™ Membrane Filters (continued) 1Monitor refills with thin absorbent pads for aerosol monitoring 2Matched weight filter pairs 3Monitor refills with thick absorbent pads for liquid monitoring 4Matched-weight monitor refills with thick absorbent pads for liquid monitoring 5Minimal fiber contamination. For asbestos monitoring applications 6Immobilon®-NC Transfer Membrane for Western blotting

Reinforced cellulose membranes (or RW filters) are rigid screen filters featuring a mixed cellulose ester membrane reinforced by a polyester web. Their rigidity, high-capacity, and low pressure drop make RW filters ideal for the removal of contaminants from heavily contaminated liquids and gasses, particularly for prefiltration. While traditional prefilter materials contain asbestos or fiberglass, reinforced cellulose membranes are produced from non-shedding materials, making them ideal for prefiltration prior to the use of sterilizing-grade (<0.2 gm) filters.

+This application only applies to specific membrane filters within the product group. Please see specific application details for the product of interest on www.sigmaaldrich.com

+This application only applies to specific membrane filters within the product group. Please see specific application details for the product of interest on www.sigmaal

Recommended for general filtration applications, cellulose nitrate membrane filters feature low extractable levels and a narrow pore size distribution. While nitrocellulose is often considered to be brittle and thermally instable, these filters offer increased strength and flexibility, as well as thermal stability up to 121 °C, allowing them to be autoclaved without shrinkage or integrity loss. Cellulose nitrate membrane filters feature high protein binding, which may result in sample loss when filtering biological samples. +This application only applies to specific membrane filters within the...

Polyvinylidene Fluoride (PVDF)Millipore® Filtration ProductsDurapore® Membrane Filters Due to their solvent and heat resistance, Durapore® polyvinylidene fluoride (PVDF) membranes are utilized in a variety of biomedical research applications. Available in both hydrophilic and hydrophobic formats, Durapore® membrane filters provide high flow rates and throughput, low extractables, and broad chemical compatibility. Hydrophilic Durapore® membranes exhibit very low protein binding and have been shown to bind less protein than nylon, nitrocellulose, or PTFE membranes. Conversely, hydrophobic Durapore®...