What is the Difference Between CN and PES Filter?

In the realm of filtration technology, CN (Cellulose Nitrate) and PES (Polyethersulfone) filters are two commonly used types of membrane filters, each with its unique properties and applications. Understanding the differences between these two types of filters is crucial for selecting the right filtration solution for specific needs.

CN (Cellulose Nitrate) Filters

CN filters are made from cellulose nitrate, a material known for its durability and chemical compatibility. These filters are typically available in pore sizes ranging from 0.2 µm, 0.45 µm, and 0.8 µm. They are widely used for general filtration of buffers and solutions in various industries.

Key Characteristics of CN Filters:

Chemical Compatibility: CN filters are compatible with a wide range of chemicals, making them suitable for use in various applications.

Durability: These filters are known for their durability and can withstand moderate levels of chemical and physical stress.

Standard Membrane: CN filters are often used as a standard membrane for general filtration purposes.

However, CN filters do have some limitations. For instance, they may have higher protein binding rates compared to other materials, which can be problematic in applications where low protein binding is required.

PES (Polyethersulfone) Filters

PES filters, on the other hand, are made from polyethersulfone, a high-performance thermoplastic material. These filters are renowned for their low protein binding, high flow rates, and low extractables. PES filters are often the first choice for sterile filtration of cell culture media and serum due to their excellent performance in these areas.

Key Characteristics of PES Filters:

Low Protein Binding: PES filters have a low protein binding rate, making them ideal for applications where maintaining the purity of the sample is crucial.

High Flow Rates: The material's hydrophilic nature allows for fast and efficient filtration, reducing the time required to process samples.

Low Extractables: PES filters are known for their low extractables, which minimizes the risk of contamination in the filtered sample.

Broad Chemical Compatibility: PES filters are compatible with a wide range of chemicals, making them suitable for use in diverse applications.

In addition, PES filters have a high degree of dimensional stability and can maintain their performance over a wide range of temperatures and pH values. This makes them particularly suitable for use in extreme conditions or in applications where high precision is required.

Comparison and Selection

When comparing CN and PES filters, it is important to consider the specific requirements of the application. For general filtration of buffers and solutions, CN filters may be sufficient. However, for applications where low protein binding, high flow rates, and low extractables are critical, PES filters are often the better choice.

Here are some key factors to consider when selecting between CN and PES filters:

Application Requirements: Determine the specific needs of the application, such as protein binding rates, flow rates, and chemical compatibility.

Sample Type: Consider the type of sample being filtered and its sensitivity to contamination.

Cost Considerations: Evaluate the cost-effectiveness of each type of filter based on the application's requirements and the volume of samples being processed.

In conclusion, CN and PES filters each have their unique properties and applications. By understanding the differences between these two types of filters, users can select the most appropriate filtration solution for their specific needs. Whether it's CN filters for general filtration purposes or PES filters for sterile filtration of cell culture media and serum, the right choice will depend on the specific requirements of the application.