A 96% cost reduction could make advanced cell-free protein synthesis far more practical for synthetic biology labs. A study in Trends in Biotechnology reports that researchers led by POSTECH developed an automated and modular platform that produces proteins in test tubes, with higher yields and a two-day preparation workflow.
The system is called i-POPFLEX, short for Purified components Optimized for Flexible protein expression using in vitro-produced translation factors. It assembles the molecular machinery that cells normally use to read genetic instructions and build proteins. In the new work, that machinery is made and combined outside living cells.
The advance matters because protein production is central to biotechnology. Researchers use proteins to test drug candidates, build enzymes, engineer therapeutics and probe how life works at the molecular level. Cell-free systems can speed that work because the reaction happens in a controlled tube, where scientists add DNA and watch the protein appear.
For years, reconstituted cell-free systems have carried a practical burden. Commercial kits are costly, while in-house preparation can take several days and demand careful hands-on work. The POSTECH-led team reports a platform that cuts preparation time from four days to two days and reaches up to 8.4-fold higher protein yields compared with commercial Protein synthesis Using Recombinant Elements kits.
A faster way to make proteins outside cells
Cell-free protein synthesis starts with a simple idea. A living cell contains ribosomes, enzymes, tRNAs, energy sources and other parts that translate genetic code into proteins. Scientists can prepare those parts in advance, then add a DNA template for the protein they want.
A common analogy is instant coffee. The main ingredients are already combined. When the user adds water, the drink is ready. In a cell-free reaction, the DNA acts like the recipe and the prepared biological machinery carries out the build.
The new platform focuses on reconstituted cell-free systems. These systems are especially attractive because their ingredients are defined and adjustable. Researchers can control which molecular parts are present, how much of each part is used and when certain steps occur.
That control has a price. Traditional reconstituted systems often depend on purified components that require time, skill and expensive reagents. Commercial kits make the process easier, but they can limit access for labs that want to run large numbers of reactions.
Professor Joongoo Lee of POSTECH described the goal plainly. “We have built an automated platform that makes cell-free protein synthesis dramatically faster and cheaper,” he said. That speed and cost shift could be important for labs that need hundreds or thousands of tests rather than one carefully prepared reaction.
How the automated system works
The POSTECH team built i-POPFLEX around individual molecular parts. According to the study, the system includes 34 translational components and a split T7 RNA polymerase. These pieces are produced in vitro and then assembled into a ready-to-use protein synthesis system.
The workflow uses automated liquid handling, a benchtop robotic approach that moves small volumes of liquid between wells or tubes. This helps standardize the steps that once relied heavily on the experimenter. It also supports parallel preparation, which is essential when many reactions must be set up at the same time.
The team also uses in-house-prepared buffer, ribosomes and tRNAs. These components help the reaction read RNA instructions and link amino acids into a growing protein. In practical terms, they form the working engine of the test-tube factory.
Automation does more than save labor. It can reduce variation between batches. For cell-free protein synthesis, small differences in preparation can affect yield, reliability and the ability to compare results across experiments.
The study reports that automation halves hands-on time and doubles overall preparation efficiency. The finished workflow produces complete systems within two days. For researchers working in fast design cycles, that time savings can change how often experiments are run.
Why modular parts matter
A central strength of i-POPFLEX is its modular design. Each component can be added, omitted, or adjusted depending on the experiment. That gives researchers a way to tune the chemistry instead of accepting a fixed mixture.
This matters because many modern biology projects require proteins that cells struggle to make. Some proteins are toxic, unstable, or difficult to fold in living organisms. A controlled tube lets researchers vary the reaction conditions directly.
The modular setup also allows genetic code reprogramming. In standard biology, sets of three DNA or RNA letters tell the cell which amino acid to add next. Scientists can alter that relationship in a cell-free system by changing the molecular parts that interpret those instructions.
Using that flexibility, the POSTECH-led team incorporated noncanonical amino acids into peptides and proteins. These amino acids go beyond the standard set used by most living organisms. They can add chemical handles, change protein behavior, or enable new forms of bioconjugation.
One example highlighted by the study involves amino acids bearing clickable moieties. These chemical groups can help link proteins to other molecules. That ability points toward engineered biomaterials and therapeutic designs that require precise attachment points.
Custom proteins for biofoundries
Biofoundries are automated facilities that combine robotics, software and biology. They often follow a design-build-test-learn cycle, where many genetic designs are built and screened in rapid succession. Cell-free systems fit naturally into that workflow.
A lower-cost platform could help biofoundries run larger experiment sets. The study notes that i-POPFLEX could support enzyme engineering, metabolic pathway prototyping and large-scale variant screening. Each use depends on quickly producing and testing many protein designs.
For drug development, custom protein synthesis can support the creation of therapeutic candidates and research tools. The ability to incorporate noncanonical amino acids may be especially valuable for antibody-drug conjugates. These therapies link a drug payload to an antibody that helps guide it to a biological target.
For enzyme engineering, the benefits are different. Researchers may want to test many enzyme variants to find one that works faster, withstands heat, or performs a chemical reaction with higher precision. A cost reduction from USD 1.36 per microliter to about USD 0.05 per microliter can expand the number of variants a lab can afford to screen.
The system also connects to the broader push for synthetic biology that is easier to automate. If biological reactions can be built as modular, standardized workflows, researchers can spend more time designing useful molecules and less time rebuilding the same basic machinery.
The road to larger-scale biomanufacturing
The study places i-POPFLEX at technology readiness level 4 to 5. That means the integrated components have been validated in a laboratory setting and are moving toward pilot-scale readiness. It remains an early-stage platform for broader industrial use.
Several challenges remain before the system can scale to very large production. Matching crude lysate costs would require bulk reagent production, better procurement and specialized equipment for high-throughput component synthesis. Larger volumes would also need improved upstream synthesis, downstream purification and quality control.
Still, the laboratory gains are striking. The platform achieved up to 8.4-fold higher protein yields than commercial kits while reducing cost 27-fold. It also shortened preparation time from four days to two days, which could make repeated experimentation more practical.
The long-term vision is a more accessible test-tube manufacturing toolkit. Thousands or even millions of assembled systems could support biofoundry-scale screening if production hurdles are solved. That would make reconstituted systems useful across more labs and applications.
For now, the POSTECH-led work shows how automation and modular design can reshape a powerful but expensive research tool. By making the molecular machinery cheaper, faster and easier to customize, i-POPFLEX brings next-generation biomanufacturing closer to routine laboratory use.
