Alireza Mashaghi adjusts the controls of a machine the size of a large refrigerator in his lab at Leiden University, where a tiny diamond—less than 100 nanometers wide—holds the power to see the invisible. This is the world’s first quantum biosensor, developed in collaboration with Dutch tech company QT-Sense, now operational in the Mashaghi lab and capable of detecting cellular changes that occur in microseconds, faster than the blink of an eye. For diseases like muscular dystrophy, cancer, Ebola, and dengue, where rapid molecular reactions dictate progression, this technology opens a new frontier: real-time, label-free observation of life’s most delicate processes.
Understanding how diseases unfold at the cellular level has long been hindered by timing and interference. Traditional methods often require labeling cells with dyes, which can disrupt the very systems scientists aim to study. But the quantum biosensor eliminates that problem. Using quantum properties of nanodiamonds and magnetic sensing, it detects minute chemical shifts without touching or altering the cell. When the environment around the diamond changes—say, a protein shifts shape or a signal fires—the diamond’s fluorescence changes in response, captured in high-resolution, real-time imaging. This allows researchers to pinpoint not just what is happening, but where and when inside a living cell.
Principal investigator Alireza Mashaghi, whose interdisciplinary work bridges biology, chemistry, and mathematics, sees this as a transformative leap. "It's incredibly important to know how a certain type of disease develops, and where exactly reactions occur because of the effect of medicine in a biological system with relation to space and time," he says. His team is already applying the biosensor to artificial disease models, with plans to expand to organs-on-a-chip and human tissue samples. Collaborations with pharmaceutical companies are underway, aiming to refine drug targets that depend on the precise location and timing of protein activity within cells.
The implications extend far beyond observation. By capturing ultrafast biological events in their natural state, the biosensor could help explain why some drugs fail or cause side effects—often because a protein behaves differently depending on its cellular neighborhood. With this tool, scientists can now watch those behaviors unfold in real time, without interference.
As the only facility of its kind in the world, the Leiden installation is setting a new benchmark. "The goal of our installation is ultimately very simple: to set a new worldwide standard for research within cells," Mashaghi says. From a single nanodiamond’s glow, a new era of cellular insight is beginning—one that sees not just deeper, but faster and clearer than ever before.