Growing large quantities of cells creates a surprisingly familiar problem: they need to breathe, and their waste needs somewhere to go. Cells consume oxygen and produce carbon dioxide. As cultures become denser, CO₂ can build up, change the acidity of the culture medium and eventually interfere with cell growth. Managing this exchange efficiently is therefore an important challenge for scaling biopharmaceuticals, cell-based foods and other forms of cell manufacturing.
Removing CO₂ From Both Sides
Mitsubishi Chemical Corporation has developed a cell culture system that tackles CO₂ in two places at the same time: dissolved in the culture liquid and accumulated in the gas-filled space above it.
Its patent application (WO2026140737A1) places special hollow-fiber membranes directly inside a culture vessel. The fibers sit at the surface, with part submerged in the liquid and part exposed to the air above. A vacuum inside the hollow fibers draws CO₂ through their walls and out of the system.
This matters because the CO₂ in the liquid and gas phases are connected. Removing it from both sides can help prevent one from continuously replenishing the other.
The membrane also lets CO₂ pass through more readily than oxygen. This means the system can remove unwanted CO₂ while retaining more of the oxygen that cells need, rather than continuously sweeping both gases out.
In experiments with HEK293 cells in a 20-liter rocking culture bag, dissolved CO₂ was 40–50% lower than in a comparison without membrane degassing. Under deliberately high-CO₂ conditions, viable cells remained after six days, while almost all cells in the comparison had died.
Figure 1. Schematic of Mitsubishi Chemical’s cell culture system. The culture bag (10) contains the culture medium and headspace, while the gas separation membrane module (12) sits at their interface. Its hollow-fiber membrane (18) is partly submerged and partly exposed to the gas phase. A vacuum system (16) draws CO₂ through the membrane and out of the culture.
Mitsubishi Applies Its Membrane Expertise
Mitsubishi Chemical is a major Japanese materials company with expertise spanning advanced materials, separation technologies and membranes. The disclosed system builds directly on that capability, using Mitsubishi Chemical's own three-layer hollow-fiber membrane module in the experiments.
It is an interesting example of established materials science being applied to a growing challenge in large-scale cell manufacturing.
Congratulations and a warm thank you to the inventor: Yoshie Tanizaki, for developing a new approach to managing the gases surrounding growing cells.
Lab Grown Technologies highlights meaningful innovations shaping the future of cellular agriculture and tissue engineering.
Join the conversation and share your thoughts on LinkedIn.
This article is based on publicly available information. Lab Grown Technologies is not affiliated with the inventors or organizations mentioned.
Work with Lab Grown Technologies
We help teams present their technology and make it visible to a highly engaged audience in food and biotech, capturing interest from people and organizations that may benefit from your solution.