2012 Collection

Lipid Removal by Depth Filters in Plasma Fractionation

We herein describe a 3M Purification Inc. depth filter media – Zeta PlusTM DELI that exhibits selective adsorptive properties for plasma lipids. Lipids plug chromatographic columns and filters during plasma fractionation steps and cause solution instability for the final product. Several parameters which could affect the lipid removal efficiency on Zeta Plus DELI have been investigated: prefiltration, contact time, ionic strength, pH, and temperature. The maximum percentage of total lipids eliminated, in optimal operating conditions, was 68%. This method has…

Evaluating AMMP Protein A Assays: Comparing Sample Preparation Methods, Ligand Performance & Assay Performance

Regulations governing the production of biopharmaceuticals require high levels of purity for processes utilizing Protein A affinity chromatography. It has been shown that Protein A in the presence of IgG forms a PA/IgG complex that interferes in the traditional immunoassay format for detecting Protein A. In this work we evaluated the AMMP Protein A Assay using two popular sample preparation methods to dissociate the ProteinA/IgG complex. The AMMP assay was also tested with Protein A ligands from multiple sources including…

A Single-Use Bioreactor for Both Cell and Microbial Cultures: A Dream Becomes Reality

Application of single-use equipment is common practice in the biopharmaceutical industrial and academic field. Compared to the traditional glass or stainless steel bioreactors, single-use bioreactors offer clear advantages: a quicker turnaround time; minimal utilities required; greatly reduced risk of cross contamination; more operational flexibility; reduced validation requirements. However, until recently, single-use bioreactors have a restricted application, only to animal cell cultures due to limitations in mixing and mass-transfer. As single-use technology not only has significant benefits for cell culture processes,…

Effect of process condition on the Mycoplasma rentention of cell culture media filtersMethods

A Mycoplasma contamination event can have a major impact on a biopharmaceutical manufacturer. The loss of a cell culture due to a contamination incurs significant costs that can be attributed to both the initial bioreactor set-up and to the subsequent decontamination. Production facility throughput may be affected and in the worst cases the ability of the manufacturer to supply patients with medicines. Mycoplasma are extremely small in size and lack a cell wall giving the cells some flexibility that enables…

Salt-tolerant cation exchanger for direct capture of proteins

Ion-exchange chromatography is widely used for the purification of biotherapeutic proteins. Usually, cation exchangers are applied in the primary capture step of proteins with alkaline pI. Conventional ion-exchange chromatography has the advantage of high-binding capacity, but it requires low salt conditions for protein binding and consequently adjustment of conductivity of clarified culture supernatant. An alternative method to maintain some binding capacity at higher conductivity levels is working at low pH condi¬tions notwithstanding that some proteins are sensitive to acid treatment.…