Whatman Sterile Mixed Cellulose Ester Membranes – 1.2 µm

Description

Sterile options available for critical applications.
Excellent contrast for easier particle detection.
Grids are nontoxic and do not inhibit bacterial growth, ensuring sample integrity.
Black plain and black gridded membranes have a mix of cellulose nitrate and cellulose acetate.
The membrane offers a high degree of internal surface area for greater adsorption of product.
Higher dirt loading capacity.
Biologically inert with good thermal stability.
No surfactants to contaminate samples.
Uniform microporous structure of membrane gives high flow rates.

Whatman mixed cellulose ester membranes are composed of cellulose acetate and cellulose nitrate. These membranes are characterized by a smoother and more uniform surface than pure nitrocellulose filters. Also, the color contrast provided by the filter surface facilitates particle detection and minimizes eye fatigue. The ME range has a lower cellulose acetate content compared to the WME range of membranes.

Eased counting process

In microbiological colony counting procedures, the color contrast between the surface and the colonies facilitates the counting process.

Plain or gridded

Many microbiological techniques include colony counting after incubation as the standard method of quantitation. Whatman gridded filters have clearly defined grid lines spaced at 3.1 mm or 5 mm intervals. The special ink used is nontoxic and completely free from bacterial growth inhibitors. Whatman black mixed cellulose esters are available plain for automatic colony counting applications, as well as gridded to assist in manual counting procedures. Black membranes provide contrast between residue or cell colors and the filter without having to counter-stain the membrane.

Sterile filters

For those laboratories preferring to use membranes sterilized by autoclaving for microbiological work, Whatman provides black gridded membranes in packs with pads ready for laboratory autoclaving.

Parameter	Mixed Cellulose Ester Circle ME Range (ME 28), green/black grid 3.1 mm, sterile, 1.2 µm pore size, 50 mm
Air Flow Rate(Delta p equals 3 mbar):	6.7 s/100 ml
Application:	The membrane is particularly effective in applications requiring higher flow rates and larger volume filtration including clarification or sterilization of aqueous solutions, particulate analysis and removal, air monitoring and microbial analysis. Other applications include: Clarification or sterilization of aqueous solutions Cytology Air monitoring HPLC samples (aqueous) Virus concentration Particulate analysis Biological assays Food microbiology including enumeration of E. coli in foods Bacteriological studies Particle counting from liquids and aerosols Yeasts and molds.
Autoclavable:	Yes
Diameter:	50 mm
Grid Color:	Green/black
Grid Dimension:	3.1 mm
Interleaving Paper:	Yes
Material:	Mixed Cellulose Ester (MCE)
Membrane Type:	ME 28
Operating temp. max.:	130°C
Pore Size:	1.2 µm
Porosity Max.:	77%
Porosity Min.:	74%
Protein Binding:	Medium
Solvent Resistance:	Medium
Sterility:	Sterile
Water Flow Rate(Delta p equals 0.9 bar):	1.2 s/100 ml/12.5 cm²
Weight Max.:	5.0 mg/cm²
Weight Min.:	4.3 mg/cm²
With Pad:	No
Pack size:	100 pieces