Example : KDA0031 cartridge add “-S” for sterile version. Datasheets available for all cartridges, please enquire.
For sterile version add “-S” to product reference (minimum quantuty applies for sterile version)
Produced in an ISO 13485 accredited facility
Pore-size rating vs molecular weight cut-off
It is important to distinguish between these important two parameters which are often confused one with other :
Pore Size Rating: Pore size rating refers to the average diameter of the openings or pores in a filtration medium, typically measured in micrometers (µm) or nanometers (nm). It represents the physical size of the spaces through which particles or molecules can pass. Pore size rating is determined based on the largest particle size that can be retained by the filter, allowing only smaller particles to pass through. It is often used as a general indicator of a filter’s sieving or size-exclusion properties.
Molecular Weight Cutoff (MWCO): Molecular weight cutoff is a specification used to characterize the molecular size selectivity of an ultrafiltation membrane. It represents the molecular weight of a solute or molecule at which it is expected to be retained to a specified % by the filter. ATTENTION : the % retention at the MWCO claimed by a manufacturer depends on the manufacturer’s rating method. KDBIO’s MWCO rating method refers to 50% retention of a globular protein of the same MW, i.e. the protein molecular weight above which more than 50% of a protein will be filtered out, with retention increasing logarithmically with increasing MW. For our 20 kDa fiber this translates to 99.9% retention at around 100 kDa. The 20kDa fiber will therefore completely retain a full-size monoclonal antibody. MWCO is commonly expressed in kilodaltons (kDa) or daltons (Da), which are units of molecular weight. There can be some correlation between pore size rating and molecular weight cutoff but they are not directly interchangeable. Factors such as molecular shape, charge, and interactions with the filter material can influence retention performance.