Sartorius, 13106--47----HCN, Cellulose Nitrate (CN) Membrane Filter

Sartorius type 131 cellulose nitrate membranes are 47 mm white filter discs with a black printed grid for microbiological membrane filtration and colony counting. The 0.45 µm pore rating and 6 mm hydrophobic edge distinguish this configuration from similar type 131 filters with other edge sizes or packaging. The membrane is hydrophilic over the filtration region and is supplied nonsterile in a bulk pack of 100. The grid supports the visual localization and counting of colonies on appropriate culture media, while the hydrophobic edge can help constrain the wetted area during filtration and subsequent handling. Use the membrane in a compatible 47 mm holder, apply the desired sample volume and transfer the filter to a validated growth medium when colony enumeration is required. Because the supplied membranes are nonsterile, do not treat the package as ready-to-use sterile microbiological consumables without an approved sterilization step. Maintain aseptic handling, include blanks and assess sample matrix effects on colony recovery. This filter is not a virus removal membrane or a universal sterilizing filter validation.