Alumina Oxide (AO) FAQ

Aluminum Oxide (AAO) membrane filters are extremely brittle and should be handled with care to prevent cracking or breakage. Sterlitech recommends using membrane tweezers rather than fingers when handling AAO membranes. For additional handling best practices, please refer to our Aluminum Oxide membrane handling guide on the Sterlitech blog - Click here

Aluminum Oxide (Anodic Aluminum Oxide, AAO) membrane filters are ideal for high-purity filtration, analytical testing, and research applications. Their inorganic structure is free of organic extractables and leachables, minimizing the risk of sample contamination. AAO membranes also exhibit very low nonspecific adsorption, helping preserve sample integrity and maximize analyte recovery. In addition, AAO membrane filters offer uniform pore size, high porosity, and excellent chemical and thermal stability, delivering reliable filtration performance, high flow rates, and reproducible results across a wide range of laboratory and industrial applications.

At this time, Aluminum Oxide (Anodic Aluminum Oxide, AAO) membrane filters are not available in custom diameters. If your application requires a non-standard membrane size, please contact Sterlitech at [email protected] to discuss your requirements and explore alternative membrane filter options.

Yes. Aluminum Oxide (AAO) membrane filters are slightly asymmetric. The shiny side has the smallest pores and faces upward in the packaging. For applications requiring the finest surface for particle capture or analysis, orient the shiny side upstream.

No. Sterlitech Aluminum Oxide (Anodic Aluminum Oxide, AAO) membrane filters are not available with a perimeter support ring. However, when handled carefully, they provide an effective alternative to ring-supported aluminum oxide membrane filters used in filtration, microscopy, and analytical applications. Careful handling during installation and removal will help prevent membrane damage.

Aluminum Oxide (Anodic Aluminum Oxide, AAO) membrane filters can be readily dissolved using sodium hydroxide (NaOH) solutions at a concentration of 1 M or higher. Dissolution can be accelerated by increasing the NaOH concentration and/or raising the solution temperature. This method is commonly used when the membrane must be removed after filtration for particle recovery, sample preparation, or microscopic analysis.

Yes. Sterlitech Aluminum Oxide (Anodic Aluminum Oxide, AAO) membrane filters can be used as an alternative to Whatman Anodisc™ filters in many filtration, microscopy, and analytical applications. Please note that Sterlitech AAO membrane filters do not include perimeter support rings, so they should be handled with additional care during installation and use to prevent damage.