Author Archives: Dennis Annarelli

In-Line Turbidity Sensors for Monitoring Process Streams in Continuous Countercurrent Tangential Chromatography (CCTC)

by , , and

A strong connection between turbidity and total suspended solids (TSS) has been linked in the past to measuring well defined particles in processes. Optical density probes have seen wide adoption in the biotechnology industry for monitoring cell growth within a bioreactor, whereas in-line turbidity sensors have been used to monitor filter performance. Turbidity measurements offer a rapid quantification of suspended solids but have not been used in the biotechnology industry for chromatographic resins. In this study, turbidity measured with equipment developed by PendoTECH was used with novel continuous chromatography technology developed by Chromatan…

September 15, 2018

Measuring Pressure at Very Low Levels with High Accuracy in Single-Use Systems: Improved Performance and Single-Use System Testing

by , , and

Measuring pressure in single-use systems (SUS) has become an integral part of both upstream and downstream bioprocess operations. Articles have been published on filtration applications (1), and integration into other SUS has been widely adopted. Additionally, information is available on low-pressure applications such as how to prevent overpressurization in single-use bioreactors (2). However, as users and applications both become more sophisticated, improved performance is sought for low-pressure applications (<1 psi) such as in single-use bioreactors. The reasons are two-fold: First,…

March 10, 2015

Novel Single-Use Sensors for Biopharmaceutical Applications

by

The increasing adoption of single-use technology in biopharmaceutical, vaccine, and cell therapy production is one indication that such technology has moved far beyond its novelty stage. Arguably, this is the preferred technology of newly developed processes. To support the continued growth of single-use systems in the biopharmaceutical industry, the ability to measure critical process parameters with single-use sensors is required. Several key single-use sensing technologies are described, including pressure, temperature, UV absorbance, and conductivity. The technology behind each is explored…

August 15, 2014

Evaluation of a New Single-Use UV Sensor for Protein A Capture

by and

As the adoption of single-use systems continues to expand beyond bags and tubing to complete process steps, a full range of sensing technologies will be needed to complement the resulting varied single-use applications. Single-use sensors must meet or exceed the performance of traditional sensing technologies in areas such as accuracy, response time, ease of use, control system integration, process compatibility, regulatory requirements, and cost. Single-use flow-through process sensors are currently available for pressure, temperature, flow, and conductivity. Here, we report…

February 1, 2013

Streamlining Downstream Process Development

by , , and

Normal-flow filtration is used throughout downstream processes for biologics including depth, sterile, and viral filtration applications. Because of its ubiquity in large-scale biomanufacturing, using the most efficient normal-flow filter media area and type can lead to significant cost savings. To determine the most effective media type and area, developers use a scaled-down process model is used in bioprocess laboratories to minimize material requirements. Constant–flow-rate filter evaluations involve direct scale-down parameters that match manufacturing-scale process conditions. This type of evaluation can…

June 1, 2011