Fighting Superbugs with Sensors: How FLASH Diagnostics is Tackling Antimicrobial Resistance

Image generated by ChatGPT, courtesy of FLASH Diagnostics

Imagine breaking your leg, going to the hospital for a routine procedure—and walking away with a life-threatening, antibiotic-resistant infection. Unfortunately, this is not just a hypothetical situation. In fact, one case study detailed by the CDC involved two patients—treated months apart in the same intensive care unit—who contracted the same antibiotic-resistant infections traced back to a contaminated hospital sink.

This kind of hospital-acquired infection is one of the growing threats fueled by antimicrobial resistance (AMR), where mere proximity to other patients or everyday hospital infrastructure can put anyone at risk. What can be done?

I had the opportunity to interview engineer-researcher Diogo Caetano, founder of FLASH Diagnostics, about a potential solution. His company seeks to change the status quo by developing a portable, rapid diagnostic platform capable of detecting resistant bacteria in under an hour—bringing preventive testing to the front lines.

From Electrical Engineering to FLASH Diagnostics

Caetano’s journey into biomedical diagnostics was anything but linear. With a master’s degree in electrical engineering and 13 years of research experience in electrical engineering and computer science, his early career centered on high-precision magnetic sensing.

“I grew up with medicine and engineering in my house—my parents are a doctor and an engineer,” Caetano explains. “I had a passion for living things but was better at engineering. Eventually, I found a way to bring both together.”

His first startup venture explored using magnetic detection for structural flaws in airplane wings. The sensors worked too well—so precise that they created regulatory headaches and, ironically, no commercial market. That failure taught Caetano an important lesson: solving a technical problem isn’t enough. There has to be a clear path to market.

By 2017, while starting his PhD at the Instituto Superior Técnico, University of Lisbon, Caetano decided he would only work on research with market potential. He entered HiSeedTech, an entrepreneurship program in Portugal, and began exploring applications for magnetic sensors in life sciences. Resistant bacteria quickly stood out as a target with enormous societal need and commercial potential.

With colleagues from biology, physics, and computer science, Caetano co-founded FLASH Diagnostics in 2021, a spin-off from research institutions INESC MN, INESC-id and Instituto Superior Técnico, University of Lisbon. Early validation came through an award competition that granted the team €10,000—just enough to secure their first patent. Soon after, the company won funding from EIT Health and later from the Portuguese Startup Voucher, as well as Portugal Ventures, a public–private investment firm supporting long-horizon startups. Today, FLASH is a five-person team (Ruben, Liliana, Cátia, Beatriz and Diogo), blending full-time staff with part-time researchers.

The Problem: Antimicrobial Resistance in Hospitals

Caetano explains the problem like this. When you go to a hospital for an emergency treatment, like a broken leg, you might be placed in the ICU or an emergency ward for a night. In those first six hours, you’re near patients colonized with multi-resistant bacteria, while your own immune system is suppressed. That’s when you can pick up infections that are hard—or impossible—to treat.

Testing every patient for resistant bacteria is prohibitively expensive with current methods. Standard PCR systems are designed for batch processing (96 samples or more), which drives up cost and turnaround time. FLASH’s goal is simple but ambitious: deliver a single-sample, cost-effective test that can give results in less than sixty minutes. Such a technology is something that hospitals would be able to deploy broadly and make an impact in the fight against antibiotic-resistant strains.

The Technology: Magnetic Sensing Meets Machine Learning

FLASH’s diagnostic platform is built on a surprising foundation: the same giant magnetoresistor sensors that once transformed the storage capacity of computer hard drives. These sensors, currently optimized and fabricated at INESC MN, are highly sensitive to changes in magnetic fields, and FLASH has adapted them to biology in a novel way. By attaching magnetic nanoparticles to bacterial DNA, the system can register the presence of resistance genes with remarkable precision. Even when genetic material is present at very low concentrations, the sensors are capable of detecting it, which is critical for early and accurate diagnosis.

This approach carries important advantages over standard molecular diagnostics. Conventional PCR machines depend on lasers, optics, and complex hardware, all of which make them expensive and difficult to deploy outside centralized laboratories. By avoiding optical components altogether, FLASH reduces both the cost and the complexity of the system. The result is a device that can be smaller, more durable, and more accessible to clinics and hospitals that lack the infrastructure of large testing centers.

To bring this technology into real-world healthcare, FLASH has combined several innovations into a single workflow. Microfluidics are used to handle and concentrate bacterial DNA, ensuring that target molecules are moved close to the sensor surface for reliable detection while keeping reagent use to a minimum. The sensing process is supported by integrated circuit chips, which make the system scalable and allow costs to fall as production increases. On the data side, machine learning methods are applied to interpret the raw signals coming from the sensors, providing real-time analysis with exceptionally high accuracy. The emphasis is on eliminating false negatives, since missing a resistant infection could have serious consequences in a hospital setting.

At present, the company is focusing its efforts on pneumonia-causing bacteria. These infections often originate in the gut but can spread to the lungs in patients with weakened immune systems, creating severe complications that are especially dangerous when antibiotic resistance is involved. The main technical hurdle is reducing the time it takes to prepare samples. FLASH is working to shorten this process to half an hour, which, when combined with a thirty-minute detection cycle, would make it possible to provide results in under one hour at the patient’s bedside.

By drawing together advances in physics, engineering, biology, and artificial intelligence, FLASH is creating more than just a new diagnostic device. It is setting the stage for a different model of infectious disease testing—one that is faster, more affordable, and better suited to the growing challenge of antimicrobial resistance.

Navigating the Valley of Death and Building Toward Impact

Like many science-driven startups, FLASH now finds itself at the precarious stage often called the “Valley of Death”—the stretch between promising research and sustainable commercial success. Much of the company’s progress so far has been fueled by public grants, which are well-suited for early-stage experimentation and technical milestones. But as founder Diogo Caetano explains, the rules change once the work shifts from academic-style research into the business of building a product. “Coming from science, we know how to manage grants and projects, but startup funding is a different world,” he says. Venture capital tends to prefer opportunities with fast payoffs, often in consumer tech or software. Deep-tech diagnostics, by contrast, require years of development, rigorous validation, and regulatory approval before they can begin to generate meaningful revenue. That mismatch makes raising capital uniquely challenging for companies like FLASH, even when the societal need is urgent and the technology shows strong promise.

To navigate this gap, FLASH is working closely with Portugal Ventures, one of the country’s most active early-stage investors, while also preparing for its next round of funding. The strategy is to blend public support with private capital in a way that keeps the company advancing toward commercialization without losing sight of its scientific integrity.

That conviction shapes FLASH’s roadmap for the years ahead. In the near term, the company aims to deliver a hospital-focused diagnostic platform within the next three to four years, giving clinicians a rapid, bedside tool to detect resistant pathogens before they spread. Looking further ahead, Caetano envisions expanding into at-home diagnostics, where patients could test themselves with the same ease they now test for COVID or glucose levels. Such accessibility would allow doctors and patients to make better, data-driven choices about when antibiotics are truly needed—and just as importantly, when they are not. By extending molecular diagnostics beyond specialized labs and into everyday decision-making, FLASH hopes to democratize access to testing, slow the overuse of antibiotics, and help curb the global rise of resistance. In this vision, the company is not merely building a product; it is working to change the culture of antibiotic use and reshape how society responds to one of the most pressing public health challenges of our time.

In a world where antibiotic-resistant infections are spreading faster than ever, FLASH Diagnostics shows how innovation can meet urgency head-on. By combining engineering ingenuity, multidisciplinary science, and a deep commitment to patient safety, the company is turning complex research into tools that can save lives. For Caetano, however, the goal has never been only about technology, investment, or even building a profitable business. The motivation runs deeper. “This is a real problem,” he says. “Everyone should be able to go to a hospital safely and not get multi-resistant bacteria. I want to solve it—but even if it’s not us, someone must.”

To learn more about FLASH and their technology, visit flash-diagnostics.com.