New drugs made from nanoparticles that can easily penetrate any interface within our bodies are a great hope in medicine. For such hopefuls to reach the market, their safety must be ensured. In this context, it must also be clarified what happens if a substance manages to penetrate the natural barrier between baby and mother, the placenta, in the body of pregnant women. | |
“Environmental toxins can also pose a major threat to the sensitive fetus if they penetrate the placental barrier or disrupt the development and function of the placenta, thus indirectly harming the fetus,” explains Tina Bürki, Empa researcher at the Particles-Biology Interactions lab in St. Gallen. | |
A team from Empa and ETH Zurich has been working for some time on the question of how this so-called embryotoxicity of substances can be determined precisely, simply and reliably. Now the team is developing a new system that will detect embryo-damaging substances without the need for animal testing. The recently launched project is funded by the Zurich-based ProCare Foundation. |
A universe in a polymer case |
|
At the heart of the process will be a polymer chip, about the length of a human finger, that houses a small universe: Human cells grow on the chip that are to model the placental barrier and the embryo under conditions that are as close to reality as possible. For this purpose, cells of the placenta are cultivated on a porous membrane to form a dense barrier, and embryonic stem cells are formed into a tiny tissue sphere in a drop of nutrient solution. | |
To simulate blood circulation, a shaker continuously tilts the chip back and forth. Test substances can be added to the maternal side of the placenta. This allows the researchers to study the transport of the test substance and the effects on both tissues. | |
“We already know that such a test system can work, as a simplified prototype was developed during a preliminary study with the Bio-engineering lab at ETH Zurich,” says Bürki. | |
What is special about this new chip is that the researchers want to improve the cell models by replacing the previously used laboratory cell lines or mouse cells with so-called primary human cells and a human stem cell line. | |
“We are working closely with the gynecological clinic of the Cantonal Hospital of St. Gallen and can isolate the cells we are looking for from placental tissue that would otherwise be discarded after birth,” Bürki explains. | |
The cells will be used to develop an improved three-dimensional placenta model. Ultimately, the embryo-placenta chip will allow the interaction of placenta and embryo to be reproduced and transport processes at the placenta as well as direct and indirect harmful effects of a substance on embryonic development to be investigated. | |
Alternative model advantageous |
|
Studies on the developmental toxicity of drugs and environmental toxins currently rely on animal experiments with pregnant mice. In the EU, for example, 840,000 animals were used in toxicity and safety research in 2017, of which nearly 100,000 were used for developmental toxicity. Thanks to the new chip, the number of these animal experiments could be significantly reduced. | |
This is not only an important goal from an ethical point of view, because the significance of a test with pregnant mice is not optimal for assessing drug safety in humans: “The placenta has a very specific structure in each species – and in mice it is correspondingly different from that in humans,” says Empa researcher Bürki. | |
Better insights can be gained from the alternative in vitro model, i.e. the new system “in the test tube”, because the new chip technology with primary human cells can more reliably map what happens at the interface between mother and child. |
Accelerating new therapies |
|
The new test system is intended as a simple and precise way to check the safety of a substance early in the development of new drugs and thus accelerate the application of new therapies. In this way, the chip supports the safe-by-design principle, which envisions the early integration of safety aspects into the innovation process. | |
The need for developmental toxicity studies in industry is also increasing for another reason: The safety of chemicals and particles in the environment needs to be clarified, as required by the current REACH chemicals regulation. “The placenta embryo chip should ultimately be a user-friendly test kit that can provide important data on potential health risks during pregnancy,” she said. | |
The project’s results are also expected to help fill knowledge gaps in understanding the placental barrier. “The chip will be a model that brings together the processes at the placenta and in the embryo. In this way, we hope to better understand the complex interactions that take place by means of signaling substances in the future,” says Tina Bürki. |

News
Scientists Discover Hidden Cause of Alzheimer’s Hiding in Plain Sight
Researchers found the PHGDH gene directly causes Alzheimer’s and discovered a drug-like molecule, NCT-503, that may help treat the disease early by targeting the gene’s hidden function. A recent study has revealed that a gene previously [...]
How Brain Cells Talk: Inside the Complex Language of the Human Mind
Introduction The human brain contains nearly 86 billion neurons, constantly exchanging messages like an immense social media network, but neurons do not work alone – glial cells, neurotransmitters, receptors, and other molecules form a vast [...]
Oxford study reveals how COVID-19 vaccines prevent severe illness
A landmark study by scientists at the University of Oxford, has unveiled crucial insights into the way that COVID-19 vaccines mitigate severe illness in those who have been vaccinated. Despite the global success of [...]
Annual blood test could detect cancer earlier and save lives
A single blood test, designed to pick up chemical signals indicative of the presence of many different types of cancer, could potentially thwart progression to advanced disease while the malignancy is still at an early [...]
How the FDA opens the door to risky chemicals in America’s food supply
Lining the shelves of American supermarkets are food products with chemicals linked to health concerns. To a great extent, the FDA allows food companies to determine for themselves whether their ingredients and additives are [...]
Superbug crisis could get worse, killing nearly 40 million people by 2050
The number of lives lost around the world due to infections that are resistant to the medications intended to treat them could increase nearly 70% by 2050, a new study projects, further showing the [...]
How Can Nanomaterials Be Programmed for Different Applications?
Nanomaterials are no longer just small—they are becoming smart. Across fields like medicine, electronics, energy, and materials science, researchers are now programming nanomaterials to behave in intentional, responsive ways. These advanced materials are designed [...]
Microplastics Are Invading Our Arteries, and It Could Be Increasing Your Risk of Stroke
Higher levels of micronanoplastics were found in carotid artery plaque, especially in people with stroke symptoms, suggesting a potential new risk factor. People with plaque buildup in the arteries of their neck have been [...]
Gene-editing therapy shows early success in fighting advanced gastrointestinal cancers
Researchers at the University of Minnesota have completed a first-in-human clinical trial testing a CRISPR/Cas9 gene-editing technique to help the immune system fight advanced gastrointestinal (GI) cancers. The results, recently published in The Lancet Oncology, show encouraging [...]
Engineered extracellular vesicles facilitate delivery of advanced medicines
Graphic abstract of the development of VEDIC and VFIC systems for high efficiency intracellular protein delivery in vitro and in vivo. Credit: Nature Communications (2025). DOI: 10.1038/s41467-025-59377-y. https://www.nature.com/articles/s41467-025-59377-y Researchers at Karolinska Institutet have developed a technique [...]
Brain-computer interface allows paralyzed users to customize their sense of touch
University of Pittsburgh School of Medicine scientists are one step closer to developing a brain-computer interface, or BCI, that allows people with tetraplegia to restore their lost sense of touch. While exploring a digitally [...]
Scientists Flip a Gut Virus “Kill Switch” – Expose a Hidden Threat in Antibiotic Treatment
Scientists have long known that bacteriophages, viruses that infect bacteria, live in our gut, but exactly what they do has remained elusive. Researchers developed a clever mouse model that can temporarily eliminate these phages [...]
Enhanced Antibacterial Polylactic Acid-Curcumin Nanofibers for Wound Dressing
Background Wound healing is a complex physiological process that can be compromised by infection and impaired tissue regeneration. Conventional dressings, typically made from natural fibers such as cotton or linen, offer limited functionality. Nanofiber [...]
Global Nanomaterial Regulation: A Country-by-Country Comparison
Nanomaterials are materials with at least one dimension smaller than 100 nanometres (about 100,000 times thinner than a human hair). Because of their tiny size, they have unique properties that can be useful in [...]
Pandemic Potential: Scientists Discover 3 Hotspots of Deadly Emerging Disease in the US
Virginia Tech researchers discovered six new rodent carriers of hantavirus and identified U.S. hotspots, highlighting the virus’s adaptability and the impact of climate and ecology on its spread. Hantavirus recently drew public attention following reports [...]
Studies detail high rates of long COVID among healthcare, dental workers
Researchers have estimated approximately 8% of Americas have ever experienced long COVID, or lasting symptoms, following an acute COVID-19 infection. Now two recent international studies suggest that the percentage is much higher among healthcare workers [...]