Development Of Low Pyrogenic Response And Ultra-Low Metal Ion Extractables Zeta Plus™ Filter Medium

Cellulose based depth filters are widely used for filtration of biopharmaceutical and blood plasma fraction therapeutics. This 3M Purification Inc. Application Brief describes development of two cellulose based depth filters (the LA and LP grades), employing a specialized grade of cellulose selected to minimize beta glucan extractables. Beta glucan is a naturally occurring component of cellulose, which can cause false positive Limulus Amebocyte Lysate (LAL) test results. In addition, the LA grade of Zeta Plus™ containing a special low beta glucan cellulose, is also constructed with pre-extracted filter aid to minimize metal ion extractables. This unique depth filter construction is ideal for biological fluid filtration where the end product is a parenteral dosage form.

The Process
Cellulose depth filters are used in initial stage blood plasma fractionation to either clarify certain Cohn process fractions or to collect precipitated protein. In biopharmaceutical processing, depth filters are frequently used for media feed filtration, for the initial cell separation process and for downstream purification stages such as chromatography column protection and following ultrafiltration steps to clarify concentrated protein solutions.