Specifications Table

Product Name – Whatman CA Membrane Filter
Quantity/Pack Size – 25MM, 0.45um (Pack of 100) | 47MM, 0.2um (Pack of 100) | 47MM, 0.45um (Pack of 100)
Form – Circular membrane discs
Grade – Cellulose acetate (CA)
Application – Sterile filtration, particle analysis, aqueous solution clarification

Product Overview

Whatman CA membrane filters are engineered from high-purity cellulose acetate, delivering consistent performance for critical laboratory filtration applications. The hydrophilic nature of these membranes ensures rapid wetting and uniform flow rates, making them ideal for aqueous solutions, buffers, and biological samples. With precise pore size options (0.2?m and 0.45um), these filters provide reliable particle retention while maintaining high throughput. The 25MM and 47MM diameters accommodate standard filtration setups, including syringe filters, vacuum manifolds, and pressure-driven systems. Their low protein-binding properties minimize sample loss, ensuring accurate downstream analysis. The membranes are chemically compatible with a wide range of solvents and solutions, excluding strong acids, bases, and organic solvents like DMSO or acetone. Each pack contains 100 sterile, individually wrapped discs to prevent contamination and ensure lot-to-lot consistency. The white, smooth surface allows for easy particle visualization under microscopy, while the robust mechanical strength resists tearing during handling. Whether used for routine sample preparation or high-sensitivity assays, these filters meet stringent quality standards for research-grade applications.

FAQs

1. What is the maximum operating temperature for Whatman CA membrane filters?

These filters can withstand continuous operation at temperatures up to 135uC, though prolonged exposure to high heat may affect membrane integrity. For autoclaving, use 121?C for 20 minutes.

2. Can these filters be used with ethanol or isopropanol?

Cellulose acetate membranes have limited compatibility with alcohols. While brief exposure to low concentrations (?30%) is acceptable, prolonged contact with high-percentage ethanol or isopropanol may cause membrane swelling or dissolution.

3. How should these filters be stored to maintain sterility?

Store the unopened packs in a cool, dry environment (15?30uC) away from direct sunlight and chemical fumes. Once opened, use the filters immediately or reseal the packaging with parafilm to prevent microbial contamination.

4. Are these filters suitable for air or gas filtration?

While primarily designed for liquid filtration, they can be used for air/gas filtration in low-pressure applications. However, their hydrophilic nature may lead to moisture absorption, reducing efficiency in humid environments.

5. What alternatives exist for organic solvent filtration?

For organic solvents like DMSO, acetone, or chloroform, consider PTFE (polytetrafluoroethylene) or PVDF (polyvinylidene fluoride) membranes, which offer broader chemical resistance while maintaining similar pore size options.