Welcome to this week's issue of Deep Tech Brief.
Every Saturday, we break down deep tech companies building genuinely hard things, in plain language. No jargon, no hype.
Three companies this week: a cleaner rocket fuel from eastern Spain, a robot that scans your heart while you lie in bed from Delft, and a way of keeping chemotherapy exactly where ovarian cancer hides, from Norway.
Let’s dive in.
1. Arkadia Space: a cleaner fuel for satellites
Most satellites carry a small tank of fuel for the thrusters that keep them in the right orbit. For more than half a century the fuel of choice has been hydrazine, according to the European Space Agency. It works very well, and it is also extremely toxic, which is why engineers put on spacesuit-like protective gear whenever they fill a satellite with it. In 2011 the EU added hydrazine to its list of "substances of very high concern", which puts a question mark over its long-term future in Europe.
Arkadia Space, based at Castellón Airport in eastern Spain, builds engines that run on highly concentrated hydrogen peroxide instead, a far stronger version of the chemical sold in pharmacies as a mild disinfectant. Its next engine pairs the peroxide with a fuel of its own that ignites the moment the two touch, which suits the quick, precise bursts satellites need. Because the propellants are easier and safer to handle, they can be loaded at the launch site rather than in specialist facilities, and the company says that cuts operating and refuelling costs by more than 60%.
It has already flown. In March 2025, Arkadia's propulsion system went up on a SpaceX rideshare mission aboard a D-Orbit satellite carrier, and by June the company had confirmed test firings in orbit that matched its ground tests. It describes this as the first hydrogen peroxide propulsion system from Europe to fly in orbit.
Where they are: co-founded by chief executive Francho García and chief technology officer Ismael Gutierrez. A €2.8 million seed round in 2023 was led by DraperB1, with Spanish astronaut Pedro Duque among the investors. In March, the company secured a €14.5 million package through the European Innovation Council, made up of a €2.5 million grant, €6 million of equity from the EIC Fund and €6 million from private investors. Customers include the European Space Agency, for which it built a 250-newton thruster, and MaiaSpace, the reusable rocket programme backed by ArianeGroup.
Worth watching, because its engine has already worked in orbit and the regulatory pressure on hydrazine is only moving one way. The milestone ahead is the larger two-propellant engine, rated at up to 500 newtons, which would open the door to bigger jobs such as docking and, eventually, lunar landings.
Learn more: arkadiaspace.com
2. Corbotics: a robot that scans your heart
An echocardiogram, an ultrasound scan of the heart, is how doctors see how well it is pumping, and it sits at the centre of diagnosing heart failure, a condition that affects about 64 million people worldwide according to the World Heart Federation. Every one of those scans is done by hand, by a trained sonographer or cardiologist guiding a probe across the patient's chest, and there are not enough of them. In the UK alone, sonographer posts have an average vacancy rate of 24%, rising to around 40% in some areas, according to figures published by ultrasound professionals this summer.
Corbotics, based in Delft in the Netherlands, has built the scan into the bed. The patient lies down, and a robotic system moves the ultrasound probe by itself, using four machine-learning models to decide where the probe should go and at what angle. The company trained them on millions of images it collected from volunteers.
The first results in people are encouraging. In a study of the first 25 patients, published this year as a conference abstract in the European Journal of Heart Failure, the robot captured 99.8% of the 41 standard views a full exam needs, in about 27 minutes on average. There were no serious device-related problems, and patients reported no real discomfort. That study tested whether the robot can capture the images, not how accurate the resulting diagnoses are, which is the next question.
Where they are: led by chief executive Adriaan van Donk, with a team of 22. The device received Breakthrough Device designation from the US Food and Drug Administration in June, and Corbotics has signed a €2.5 million European Innovation Council Accelerator grant. Clinical studies with more than 300 patients are under way at four Dutch hospitals, and in August it agreed a distribution partnership with Us2.ai, whose software analyses heart scans automatically. The device is not yet CE marked.
One to watch, carefully. Promising first human data, a breakthrough designation and a partner already lined up for the analysis side make a strong start for a company of this size. The milestone ahead is showing that the robot's scans lead to the same diagnoses an expert's would, and then the CE mark that would let hospitals buy it.
Learn more: corbotics.com
3. NaDeNo: keeping chemotherapy where the cancer is
Ovarian cancer killed about 207,000 women in 2022, according to the World Cancer Research Fund. It is often found late: around 70% of patients are diagnosed at an advanced stage, and around 70% relapse after surgery and first-line chemotherapy, according to a 2016 clinical review. Part of the reason is that the cancer spreads across the lining of the abdomen as tiny clusters of cells that are very hard to find and remove.
Standard chemotherapy goes into the bloodstream and travels around the whole body. Those small deposits in the abdomen have a poor blood supply, so relatively little of the drug reaches them, according to the EU's description of the company's project.
NaDeNo, a spin-off from the Norwegian research institute SINTEF built on more than ten years of nanomedicine research, takes a more direct route. It packs a chemotherapy drug, cabazitaxel, into tiny particles and delivers them straight into the abdominal cavity, where they spread out and stay put, releasing the drug where the hidden cancer cells are. In animal studies, the company reports 100% survival and a 97% reduction in tumour weight compared with the same drug given without the particles.
Where they are: co-founded by chief executive Annbjørg Falck and chief technology officer Ýrr Mørch, and based in Trondheim. In February it was one of 61 companies, out of 923 applicants, selected for the EIC Accelerator, worth up to €10 million in total: a €2.5 million grant plus up to €7.5 million in equity. The money is meant to take its lead drug, PACAB-002, through a first clinical trial in women whose ovarian cancer has responded to standard treatment but who remain at high risk of relapse. The EU project description puts the start of that trial in the second half of 2026.
One to watch, carefully. It goes after the moment that matters most in ovarian cancer, just after treatment seems to have worked, and the animal results are striking. The milestone ahead is that first human trial, which has to show the approach is safe in patients before anyone can talk about relapse rates.
Learn more: nadeno.com
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See you next Saturday.
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