Scientists have developed a powerful new sensor that uses light to detect extremely tiny signs of cancer in the blood, raising hopes for earlier diagnosis through a simple blood test.
The technology is designed to spot cancer-related molecules long before symptoms appear or tumors can be seen on medical scans.
Many diseases, including cancer, release small biological markers into the bloodstream.
These biomarkers can include proteins, fragments of DNA, or other molecules that signal the presence of disease.
The challenge is that at the earliest stages, these markers exist in incredibly small amounts, making them difficult to detect with current methods.
A research team led by Han Zhang at Shenzhen University in China has created a sensor sensitive enough to identify these faint signals.
Their study, published in the journal Optica, shows the device can detect lung cancer biomarkers in patient samples even when only a few molecules are present.
The new sensor combines several advanced technologies. It uses specially designed DNA structures, tiny light-emitting particles called quantum dots, and CRISPR gene-editing tools.
Together, these components allow the device to detect molecular changes using a light-based technique known as second harmonic generation, which produces a clear signal with very little background interference.
Unlike many existing tests, the new method does not require complicated steps to amplify the target molecules. Traditional techniques often need time-consuming chemical processes to boost the signal before detection is possible. By contrast, this sensor can directly measure biomarkers at extremely low concentrations, making the process faster and potentially cheaper.
In experiments, the researchers tested the device on a biomarker called miR-21, which is linked to lung cancer. After confirming that it worked in simple laboratory solutions, they successfully detected the same marker in blood serum from cancer patients. The sensor also showed high accuracy, responding only to the target molecule while ignoring similar ones.
Experts say this kind of technology could transform how diseases are diagnosed and monitored. Earlier detection of cancer usually leads to better treatment outcomes and higher survival rates. The sensor might also allow doctors to track how well treatments are working by measuring biomarker levels regularly, rather than waiting months for imaging tests.
Beyond cancer, the system could be programmed to detect a wide range of health threats, including viruses, bacteria, or markers linked to neurological diseases such as Alzheimer’s. Because the DNA components can be customized, the sensor could be adapted for many different conditions.
The research team is now working on shrinking the technology into a portable device that could be used in clinics, hospitals, or even remote areas with limited resources. If successful, this approach could one day make early disease screening as simple as a routine blood test, helping doctors intervene sooner and improving patient outcomes.
While more testing is needed before it reaches everyday medical use, the study highlights how combining biology, nanotechnology, and optics could open a new era in early disease detection.
