One of the lowest protein binding filters available and naturally hydrophilic, Cellulose Acetate filters are commonly utilized to filter aqueous solutions and some organic solvents in addition to providing cell retention for liquid, light scattering measurement, and sterilization. If you’re looking to select a CA filter, it is important to take into consideration the variety of factors that will determine the correct filter for your application. We’ve highlighted the common characteristics, benefits, and common applications of cellulose acetate filters below so read on to find out.
What to Know About Cellulose Acetate Filters
Cellulose acetate filters are derived from acetylated cellulose which allows a high flow rate and thermal stability with low adsorption characteristics. It is both cellulosic and thermoplastic and largely stable in the face of mineral and fatty oils.
Cellulose acetate filters are able to easily bind with proteinaceous solutions. Because of this, they are used in many applications such as blood products and medical waste disposal. They also have a high affinity for lipids and other soluble molecules, which makes them useful for a broad range of applications including pharmaceuticals, cosmetics, food processing, water purification, and industrial fluids.
When to Use Cellulose Acetate Filtration
It is highly recommended to use cellulose acetate membrane filters for applications requiring low protein bonding, coarse particle removal, filtering culture media containing sera, diagnostic cytology, and clarifying aqueous solutions including sterilization and ultra cleaning.
Cellulose Acetate Membrane Filters vs. Cellulose Acetate Syringe Filters
Cellulose acetate membrane filters are used in applications that require high flow rates and a high level of filtration. They have a very low dead space volume, so they can be used to filter many different types of liquids including water, alcohols, acids, alkalis, and organic solvents. They can also be used to filter air or gasses such as nitrogen or carbon dioxide.
Syringe filters are made from cellulose acetate, but the process for making them involves injection molding rather than extrusion blowing. This results in a more porous structure with larger pores than other kinds of cellulose acetate membranes. These membranes can be used for applications where there is not much pressure difference between the upstream and downstream sides of the membrane due to low flow rates and/or low viscosity solutions such as dialysis applications involving blood plasma separation or medical solutions like intravenous solutions.
Cellulose Acetate Membrane Roll Stock
Cellulose acetate membrane roll stock is a thin, flexible sheet of cellulose acetate that can be wound onto a core. It is used in applications where low filtration resistance and high flow rates are important. Roll stock is a filter subcategory of membrane filters.
Benefits of Cellulose Acetate Filters
- Withstands Temperatures Up to 356℉
- Naturally Hydrophilic
- Strong Thermal Stability
- Low Protein Binding
Withstands Temperatures Up to 356℉
Cellulose acetate filters are durable in the face of high heat and can withstand temperatures up to 356℉ making them a suitable choice when dealing with hot gasses.
Hydrophilic cellulose acetate allows water to easily pass through for filtration of aqueous substances and sera.
Strong Thermal Stability
Thanks to the ease of oxidation, cellulose acetate filters enjoy the strongest thermal stability of any cellulose derivatives.
Low Protein Binding
Because the cellulose acetate membrane does not absorb protein, protein is easily sorted and filtered even when it has very low levels of protein. This is especially useful within medical applications when in contact with blood, enzyme solutions, tissue culture media and serums, and other applications where recovering protein is prioritized.
Cellulose Acetate Application
In addition to the applications mentioned above, cellulose acetate is useful in the following applications:
- Protein/ Enzyme filtration
- Steam Filtration
- Chemical Industry
- Pharmaceutical Industry
- Vacuum Filtration
- Smoke Filtration
Types of Cellulose Acetate Filters
Additional capabilities and features can be found within the wide range of diameter, prefilter, and pore sizes available. These range in 13mm to 293mm diameters and 0.22um to 8um pore sizes. Because of the wide range of size, cellulose acetate membrane filters are able to be utilized in an even wider array of applications for improved scientific benefit.
How to Select a Hydrophilic Cellulose Acetate Filter
Selecting a hydrophilic cellulose acetate filter can be overwhelming. Luckily, there is a prescribed process that includes four simple steps which are able to be performed with a filter media selector. These steps include:
- Determining the need for prefiltration based on desired application
- Navigating the qualities required for membrane filtration which can include; aqueous, non-polar, and protein subcategories
- Selecting a diameter type from a range of options including <10mL, <100mL,or <250mL. This will determining the mm diameter of the filter
- Based off of the micron size of a column of either >3um or <3um to determine the pore size
In determining the filter that is right for you it is also absolutely essential to ensure the chemical compatibility of the filter is followed. Cellulose acetate has low chemical compatibility. Consider the Membrane Filter Chemical Compatibility Chart when purchasing your filter for the different materials that cellulose acetate is fully compatible with:
- Phosphoric, 25%
- Trichloroacetic, 10%
- Ammonium Hydroxide, 25%
- Most Alcohols
- Benzyl Benzoate
- Isopropyl Myristate
- Tricresyl Phosphate
- Ethyl Ether
- Isopropyl Ether
- Monochlorobenzene, Freon
Cellulose Acetate Filters Are Designed to Meet Your Needs
If you are looking for a chemical-resistant material that can be used for many applications, the cellulose acetate filter is a great choice. It offers high purity and the ability to withstand high temperatures. The cellulose acetate filter is also resistant to acids, alkalis, alcohols, oils and fats, salts, most solvents, and many other chemicals.
Our cellulose acetate membrane filters and syringes are high quality, efficient, and affordable. With a variety of applications available, the most important step is ensuring that your desired outcome is able to be accurately expected.