Anodisc 25mm 0.2 µm Aluminum Oxide Membrane Filters, Pack of 50
The Anodisc aluminum oxide membrane filters are suitable for use in a wide range of specialized applications, including HPLC mobile phase filtration and degassing, bacterial analysis by epifluorescent light microscopy, ultra cleaning of solvents, gravimetric analysis and liposome extrusion. The tightly controlled pore size found in these membranes results in the most controlled filtration media available. There are no "doublets" or "triplets" and the very high pore density makes possible filtrations in a fraction of the time as what would be otherwise required.
Pore size: 0.2µm; 200nm
Pore density: 109/cm2
Surface Porosity: 25-30%
Top view of a 0.2µm ANOPORE™; inorganic membrane (top photo) and a cross-sectional view (bottom photo) showing 0.23µm latex microspheres retained on the membrane's surface. Membrane thickness approximately 60µm. Note the extraordinarily high pore density, which makes possible otherwise unheard of flow rates for this small of a pore size membrane filter.
A word about semantics: Technically speaking, the raw sheet aluminum oxide membrane material is what is called ANOPORE inorganic membrane, but once it is cut out into discs, it is then called the Anodisc™; Membrane Filter.
The Anodisc™; inorganic membrane is fabricated from a unique form of aluminum oxide with a highly controlled, uniform capillary pore structure. Advantages over polymer membranes are many, including:
- High flow rates.
- Extremely efficient particle retention.
- Provides a rigid, uniform surface for cell attachment and growth.
- Transparent when wet, enabling easy light microscope evaluation of cell growth. (1.60 +/- 0.01 refractive index when wet.)
- Retains virtually no background stain and is therefore ideal for all staining techniques including fluorescence and immunofluorescence.
- Lowest levels of extractable materials for minimum interference in delicate experiments.
- Sieving of particles at the surface rather than trapping at an uncertain depth within the membrane.
- Temperature and electron beam radiation resistant.
- Ideal beam-stable substrate for SEM examination.
- Smallest pore size available in any controlled pore size filtration media.
- Membrane thickness approximately 60 µm for all three pore sizes
- Membrane filters are stable to 400° C/ 752° F in terms of retaining their filtration properties but above that point, the high surface area gamma alumina will start a transformation process to the lower surface area alpha alumina. However if the filter is just being used as a high temperature substrate for heating and annealing studies, then so long as the substance being annealed will not react with the alumina substrate, then there should be some higher range where the membranes still have some practical utility.
The Anodisc aluminum oxide membrane filters are available in three nominal sizes (47 mm, 25 mm and 13 mm diameter) and three pore sizes (0.2 µm, 0.1 µm and 0.02 µm).
Ideal for Microscopic Analysis
The sieve-like properties of the Anopore membrane enable microorganisms and particles retained on the membrane surface to be examined under an electron microscope. Additionally, the membrane is virtually transparent when wet, permitting examination by light microscopy without the need to transfer the retained material, a step that could very easily result in sample loss. We know that for most, it would be high temperature or aggressive media applications that would cause aluminum oxide membranes to come first to mind, however, we have since learned that the transparency feature in fact is the reason for the largest volume of the sales of this line of products.
Aluminum oxide membrane filters are non-cytotoxic, and were tested to USPXXI Class V and BS5736 Parts 1-5.
Holding the membrane filters:
All membrane filters, offered by SPI Supplies, irrespective of their construction, must be used in conjunction with a specially made membrane filter holder.