---
title: pDS inserts - production-scale mixing in the lab | p4b
description: 3D-printed inserts that reproduce large-scale mixing times in Ambr® 250, Labfors, Minifors and DASGIP vessels. ISO 13485, custom designs in < 8 weeks.
image: https://www.p4b.io/hubfs/raw_assets/public/p4b/images/og-default.png
---

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[**pDS inserts**Large-scale conditions in your lab bioreactor](https://www.p4b.io/pds?hsLang=en) [**Advanced CFD**Gradients, lifelines and cell experiences](https://www.p4b.io/cfd?hsLang=en) [**DREAM-bio**Find the best geometry for your bioreactor](https://www.p4b.io/dream-bio?hsLang=en) [**Ambr 250 vs. 2,000 L**Interactive CFD comparison of the mixing](https://www.p4b.io/compare?hsLang=en)

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[Home](https://www.p4b.io/?hsLang=en) / Products / pDS inserts

pDS - perfect DownScale

# Production-scale mixing in your lab bioreactor

A 3D-printed insert slows mixing in your bench-scale vessel to match your target production reactor. Same vessel, same impeller, same workflow - with gradients that reflect what your cells will experience at scale.

[Request a quote](https://www.p4b.io/pds#configure)[See the 3D model](https://www.p4b.io/pds#inside)

**ISO 13485**certified inserts

**\< 8 weeks**for custom inserts

**Patented**pDS technology

Tracer mixing (CFD): 1.6 L lab reactor, the same reactor with pDS, and a 54 m³ production tank.

How it works

## From target scale to test run

Every project starts with two reactors: the bench-scale vessel you run today and the production reactor it should represent - its volume, impellers, gassing and the operating point of your process. If the mixing behaviour of the large tank is not known, we simulate it first. That behaviour becomes the design target.

The insert is not drawn by hand. Our design software places randomised structure elements in the vessel and evaluates every candidate by CFD - mixing time, power input, shear and kLa. The best candidates are combined and evolved over several generations until the insert reproduces the target, always keeping the zone around the stirrer free.

Before delivery, the design is checked in the real vessel: a pH indicator shows how long the colour change takes, and we compare that with the CFD of the target reactor. The printed insert - ISO 13485 certified, autoclaved, single use - slides into your standard vessel in about a minute.

From then on you run your process as usual, with the same stirrer, probes and control strategy. The difference is what your cells experience: the gradients of production scale, at the cost of a bench-scale run.

Ambr 250, pH indicator: about 4 s without insert, more than 30 s with an off-the-shelf insert.

3 L reference, 3 L with pDS and a 2,000 L XCellerex (CFD) - the insert brings the mixing time to large scale.

Fitting an insert into an Ambr 250 vessel - one minute, no tools.

The idea

## Bring the large tank into the lab

If small reactors mix too fast, slow them down. A 3D-printed structure inside the standard vessel stretches the mixing time to that of the production reactor - stirrer, sensors and headplate stay as they are.

Example structure from a design run - not a product insert.

![3D-printed pDS inserts next to Ambr 250 vessels](https://www.p4b.io/hubfs/website/pds-family.webp)

Loading 3D model…

Generated structure - selected by CFD

Original stirrer & headplate

Standard Ambr 250 modular vessel

Assembled

Exploded

Cross-section

Drag to rotate

**~4 s → ~37 s**until half of the liquid in an Ambr 250 is mixed - without and with insert. A 2,000 L XCellerex needs ~38 s (CFD)

The structure divides the vessel into zones that exchange liquid slowly, while stirrer, probes and control strategy stay unchanged. With three inserts - S, M and L, from about 18 to 50 s until half of the liquid is mixed - one set of parallel Ambr 250 runs covers several scales at once.

[See the CFD comparison →](https://www.p4b.io/compare?hsLang=en)

Which of your processes would you test first?

[Configure an insert set](https://www.p4b.io/pds#configure)

Scale as a DoE parameter

## Add scale to your DoE

Make mixing time a design factor. An insert set lets you test your process under conditions representative of several scales in one lab campaign - so you can assess its response to scale before it leaves the development phase.

ExampleInsert set for Ambr® 250 - four conditions side by side*relative mixing time*

Standard vessel

### Lab reference

Fast mixing, homogeneous conditions - your current baseline.

pDS insert A

### Short mixing time

Mild gradients, as in pilot-scale reactors.

pDS insert B

### Medium mixing time

Pronounced gradients of large-scale vessels.

pDS insert C

### Long mixing time

Production-scale gradients of O2 and nutrients.

- See which parameters are sensitive to scale
- Find operating windows that hold at production scale
- Fix issues while they are still cheap to fix

**2,000 L → 3 L**large-scale mixing behaviour reproduced at bench scale

**\< 8 weeks**lead time for custom inserts

**ISO 13485**certified, medical-grade inserts

[Configure your DoE set](https://www.p4b.io/pds#configure)[How pDS inserts work →](https://www.p4b.io/pds?hsLang=en)

Choose your insert

## Off-the-shelf, as a DoE set, or designed for your target

If you use Ambr 250 vessels, you can get started with standard inserts. To assess your process’s sensitivity to scale, test several mixing times in one experiment. If you want to reproduce the mixing conditions of a specific production reactor in the lab, we design a custom insert for that target.

### [![Wireframe of a pDS insert for the Ambr 250](https://www.p4b.io/hubfs/website/pds-wireframe-white.webp) Standard product · Ambr 250 modular & HT Off-the-shelf inserts Generic large-scale conditions for the Ambr 250 modular and HT vessels - order and start screening for scale effects right away. Request a quote →](https://www.p4b.io/pds#configure)

### [For process development DoE sets Several inserts with increasing mixing time, run in parallel - make scale a factor of your design of experiments. Request a quote →](https://www.p4b.io/pds#configure)

### [![Custom pDS insert designed for a bench-scale vessel](https://www.p4b.io/hubfs/website/pds-custom.webp) Custom design · \< 8 weeks Custom target inserts Designed by CFD for your vessel and your production reactor - for any bench-scale system that can be opened. Request a quote →](https://www.p4b.io/pds#configure)

Request a quote

## Works with the bioreactor you already have

If you can open the vessel, we can design an insert for it. Pick your system and tell us what you want to find out - Lena comes back to you with a proposal.

| System | Availability |
| --- | --- |
| Ambr® 250 modular / HT | Off the shelf standard inserts and DoE sets |
| Labfors | Custom realised, more on request |
| Minifors 2 | Custom designed per vessel |
| DASGIP 1.0 L / Bioblock | Custom designed per vessel |
| Other bench-scale systems | On request any vessel that can be opened |

### Configure your insert set

Inserts are available for all bench-scale systems that can be opened.

Your system Ambr® 250 modular Ambr® 250 HT Labfors Minifors 2 DASGIP 1.0 L DASGIP Bioblock Other bench-scale system

Insert set

DoE set - three mixing timesProbe how sensitive your process is to scale Single target insertMimic one specific production reactor

Request a quote →

![pDS inserts next to Ambr 250 vessels](https://www.p4b.io/hubfs/website/pds-family.webp)

White paper · CHO demonstration case

## Large-scale conditions in a 1 L lab bioreactor

How a reactor designed by generative AI recreates the gradients of a 10,000 L scale in a 1 L vessel - and what they do to lactate and mAb titer in a CHO process. 4 pages, free.

[Download the white paper](https://share-eu1.hsforms.com/1Iz-e9dcFQYax4uBfRa8fiw2dmt7m)

FAQ

## Questions we hear often

Which bioreactors can be fitted with a pDS insert?

Any bench-scale vessel that can be opened. So far we have built inserts for Labfors, Minifors, DASGIP and Ambr 250 vessels. Inserts for the Ambr 250 modular and HT vessels are available off the shelf; for other vessels we design a custom insert in under 8 weeks.

Does anything stick to the insert?

No - we have seen no build-up in E. coli, CHO or stem cell cultures. Filamentous fungi have not been tested yet; if that is your system, we would like to test it together with you.

Do cells or particles settle in the structure?

Not so far - in our cultures we have not found cells or other suspended material settling in the structure. If your process uses microcarriers or other particles, we check this with you before the first run.

Does the insert change the shear stress on my cells?

The 99th percentile of the energy dissipation rate stays the same with the insert. The highest energy input is around the stirrer, and that zone is kept free of structure.

How is the insert sterilised - is it reusable?

Inserts are made of nylon, single use and autoclaved before use, together with your standard vessel preparation. They are supplied as ISO 13485 certified, medical-grade parts.

How is an insert designed?

We generate randomised structure elements inside the vessel and evaluate each design by CFD - mixing time, power input, shear and kLa. The best designs are selected and evolved over several generations until the target mixing time is reached, then 3D-printed.

Do I need process data or CFD know-how?

No. The pDS system is host and product agnostic and does not rely on large data sets. We need your vessel, your operating conditions and the production reactor you want to represent.

Does pDS replace runs at production scale?

No - and it should not. It moves the discovery of scale effects to the lab: you find out early which parameters are sensitive to scale and can fix issues while they are still cheap to fix, so the large-scale runs confirm instead of surprise.

Get in touch

## Accelerate your process development.

Let’s discuss how p4b can help your team accelerate process development and bring your product to market faster.

[Request a quote](https://www.p4b.io/contact#quote)[Book a 30-min call](https://www.p4b.io/contact#meeting)

![Lena Achleitner](https://www.p4b.io/hs-fs/hubfs/website/team/lena-avatar.webp?width=84&height=84&name=lena-avatar.webp)

**Lena Achleitner**Senior Bioprocess Engineer, Key Account Manager[lena.achleitner@p4b.io](mailto:lena.achleitner@p4b.io)

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CFD results, case studies and new insert systems when we publish them. Unsubscribe any time.

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#### Products

- [pDS inserts](https://www.p4b.io/pds?hsLang=en)
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- [DREAM-bio](https://www.p4b.io/dream-bio?hsLang=en)
- [Request a quote](https://www.p4b.io/contact#quote)

#### Company

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