Removability and Permeability of DNA in a Solution by Cuprammonium Regenerated Cellulose Hollow Fiber (BMMTM) for Process Validation of Purification Process of Bio-Drugs

The removability and/or permeability of DNA by the BMM virus removal filter was investigated as a function of the dispersion state of DNA in a bio-drug solution. Isolated DNA of various molecular weights and packaged DNA in a virus were filtered by BMM. Dead-end filtration was performed under a constant transmembrane pressure (TMP) of 200 mm Hg. After filtration, the DNAs captured by BMM were observed by transmission electron microscopy (TEM). In the case of BMM with a mean pore size of 15nm (BMM15), the permeability of the isolated DNA was more than 0.90 when the molecular weight was less than 107. Packaged DNAs in the virion were removed at over 5 of the logarithmic rejection coefficient. Electron microscopic observation showed that DNAs were elongated by the flow of the solution through BMM. It was concluded that the removal and reduction of contaminating DNA in bio-drugs needs to allow for the dispersion state of DNA in the solution.