New biosensor uses light and AI to detect cancer in its earliest stages

Dr. Ho Sang Jung and his research team from the Advanced Bio and Healthcare Materials Research Division at the Korea Institute of Materials Science(KIMS) have developed an optical biosensor capable of detecting trace amounts of cancer cell DNA in the bloodstream with high sensitivity, enabling early cancer diagnosis. Compared to conventional liquid biopsy techniques, this biosensor offers superior sensitivity and specificity, and its standout feature lies in its ability to diagnose cancer early using only light signals and AI-based analysis, without the need for complex testing procedures.

When cancer cells develop, subtle chemical changes occur on the surface of DNA in the bloodstream-a phenomenon known as DNA methylation. In the early stages of cancer, the concentration of methylated DNA is extremely low, making it difficult to detect with conventional biosensors at high sensitivity. To overcome this challenge, the research team developed a biosensor material technology that enables the detection of methylated DNA using high-sensitivity optical signals and artificial intelligence analysis, without requiring additional processing or complex analysis steps.

The research team integrated high-sensitivity optical signaling and artificial intelligence analysis with plasmonic materials. These materials can amplify the optical signals of DNA molecules by more than 100 million times in response to light, enabling the detection of even extremely small amounts of DNA. As a result, the biosensor is capable of identifying methylated DNA at concentrations as low as 25 fg/mL (femtograms per milliliter) in the early stages of cancer development. To put this in perspective, 25 fg/mL is equivalent to dissolving 1/25,000th of a sugar grain in a single drop of water. This represents a 1,000-fold improvement in sensitivity compared to conventional biosensors.

The research team applied the developed biosensor to blood samples from 60 colorectal cancer patients, achieving a 99% accuracy rate in detecting the presence of cancer. Moreover, the biosensor successfully distinguished between cancer stages from Stage I to Stage IV with high precision. The analysis required only 100 μL (microliters) of blood and was completed within 20 minutes, demonstrating a highly simple and rapid diagnostic process.

This technology enables the high-sensitivity detection of trace amounts of cancer DNA without any pre-processing, making it highly competitive for use in the early cancer diagnosis market. Compared to conventional equipment, it significantly reduces both analysis time and cost, allowing for potential application in hospitals, health screening centers, at-home diagnostic kits, and portable diagnostic devices. It is not only suitable for precision medicine, but also highly effective for Point-of-Care Testing (POCT) applications.

This technology serves as a next-generation diagnostic platform capable not only of early cancer detection, but also of predicting prognosis and monitoring treatment response."He added, "We plan to expand its application to a wide range of diseases, including autoimmune disorders and neurological conditions."

Dr. Ho Sang Jung, Senior Researcher at KIMS and lead of the project

This research was funded by the Bio & Medical Technology Development Program and the Global Young Researcher Program of the National Research Foundation of Korea (NRF), as well as the basic research program of the Korea Institute of Materials Science (KIMS). The results were published on May 9 in the May 2025 issue of Advanced Science (Impact Factor: 14.3), a world-renowned scientific journal.