A two-step process was developed to both enhance filtration capacity (25-fold) and achieve high clearance of small-size viruses (LRV >5) using appropriate pre-filter paper.

PR772 has been chosen by the Parenteral Drug Association virus filter task force to be the model bacterio-phage to standardize nomenclature for lager-pore-size virus filters. This phage is stable, easy to handle, and high phage titers can be readily obtained.

The Viresolve NFR filter was designed to meet the critical requirement of manufacturing a safe and virus-free therapeutic by retaining RVLPs by a minimum of six log reduction value (LRV).

To determine a common endpoint definition and target LRV, a filtration matrix was designed varying phage preparation procedures (crude vs CsCl-purified), phage spike titer (106 or 108 pfu/mL), BSA quality (five sources), and co-spiking with 103 to 104 pfu/mL PR772 (Table I).

Nov 19, 2020 · Here we present a dataset of 285,944 diffraction patterns from aerosolized Coliphage PR772 virus particles injected into the femtosecond X-ray pulses of the Linac Coherent Light Source (LCLS)....

Previously, the coliphage PR772 (Tectiviridae family) has been used in some filtration studies as a surrogate for mammalian viruses of around 50 to 60 nm. In this report, we describe specific properties of PR772 critical to the support of its use for the standardization of virus filters.

Feb 10, 2018 · Fig. 2 B shows that Capto Adhere is able to clear bacteriophage in the model mAb feedstock (LRV of >3) for the first fraction in a high salt mobile phase condition for PR772 and PP7.

In summary, PR772 appears to be an appropriate model bacterio-phage for standardization of nomenclature for larger-pore-size virus-retentive filters. Virus filtration is a critical operation during the manufacture of recombinant proteins, monoclonal antibodies, and plasma-derived biopharmaceuticals.

In 2005, the task force successfully developed a rating system for large virus-retentive filters based on retention of a medium-sized bacteriophage, PR772 (11–13). Since then, the task force was charged to develop a general protocol for small virus-retentive filters.

Features ≥ 3 log reduction value (LRV) for 20 nm viruses ≥ 6 LRV for ≥ 50 nm viruses Robust size exclusion mechanism Narrow pore size distribution Low binding for high protein yields