p4b insights

Same reactor, same speed, eleven mixing times

p4b team — Fri, 23 Oct 2026 06:08:31 GMT

Mixing time is usually measured by releasing a tracer into the running flow and following how it spreads. Once the tracer concentration is within ±5 % of the average concentration, the vessel is considered mixed. In the Eppendorf DASGIP vessel we simulated, this takes around 20 seconds.

Validation first: can CFD rank stirrer positions by kLa?

p4b team — Fri, 23 Oct 2026 06:08:26 GMT

Validation is useful when it survives a hard case. We took a 2 L lab-scale bioreactor and kept the reactor, rpm and gassing the same, changing only the stirrer position. At 1.5 vvm and 1400 rpm, this was far from a clean textbook case.

Introducing DREAM-bio: exploring whole bioreactor design spaces

p4b team — Fri, 23 Oct 2026 06:08:21 GMT

Exploring a design space with different geometries, operating conditions and configurations can easily mean a few hundred simulations. Done by hand, that usually takes weeks: each setup needs manual changes, each run needs validation, and each result needs sorting and comparison. DREAM-bio makes the design space itself the input.

We expected 100 rpm to mix fastest. It didn't.

p4b team — Fri, 23 Oct 2026 06:08:16 GMT

We ran a CFD study on a 2000 L single-use bioreactor system similar to a Cytiva XCellerex setup, with a side-mounted impeller and gassing from below. Aeration was 0.1 vvm, which is a bit on the high side for mammalian processes, and the stirrer speed ranged from 50 to 100 rpm. All cases were full gas-liquid simulations in Siemens M-Star CFD.

Scaling down the physics, not just the volume

p4b team — Fri, 23 Oct 2026 06:08:10 GMT

The University of Stuttgart ran a mixing experiment (pH shift) followed by a CHO process with our downscale inserts. The 3 L reference reactor without an insert mixed in a few seconds. The same 3 L reactor with our insert took about 30 seconds, and a 2000 L XCellerex also takes about 30 seconds, based on CFD and tracer data.

When 4 seconds become more than 30: off-the-shelf pDS inserts for the Ambr250

p4b team — Tue, 18 Aug 2026 08:00:00 GMT

The Ambr250 is one of the most widely used single-use bioreactor systems for mammalian process development. It enables high-throughput process screening, but production-scale bioreactors behave very differently. They mix more slowly, which exposes cells to concentration gradients that are largely absent at small scale.

p4b at the BioProScale Symposium

p4b team — Thu, 30 Apr 2026 08:00:00 GMT

Manfred Satzer and Lena Achleitner represented p4b at the BioProScale Symposium.

pDS reactors featured in a peer-reviewed article on Zika vaccine production

p4b team — Thu, 24 Jul 2025 08:00:00 GMT

An exciting milestone for p4b: our technology is now featured in a peer-reviewed article.