Researchers have developed a machine learning approach to improve portable biosensors for detecting microcystin-lysine-arginine (MC-LR), a deadly toxin released by cyanobacteria during harmful algal blooms in freshwater systems.

Screen-printed carbon electrode biosensors offer rapid, inexpensive detection without requiring laboratory infrastructure. However, their accuracy depends on proper calibration. The team applied machine learning algorithms to optimize sensor calibration, enhancing the device's ability to identify MC-LR at dangerous levels.

MC-LR poses severe health risks even at low concentrations. The toxin damages the liver and increases risk of liver and colon cancer. The World Health Organization established a drinking water guideline of 1 microgram per liter, reflecting the compound's potency. Current detection methods often rely on expensive laboratory equipment and trained personnel, limiting their use in remote or resource-limited areas where contaminated water poses the greatest threat.

Portable SPCE biosensors address this gap by enabling on-site testing. The electrochemical detection principle requires minimal power and generates results within minutes. Yet traditional calibration methods introduce variability that reduces reliability. Machine learning algorithms can process sensor response data and correct for environmental factors, electrode degradation, and manufacturing inconsistencies that plague these devices.

By training algorithms on multiple sensor datasets, researchers created models that predict MC-LR concentration from raw electrochemical signals with greater accuracy than conventional calibration curves. This approach accommodates the natural variation between individual sensors, allowing each device to function reliably despite minor manufacturing differences.

The advancement addresses a critical monitoring challenge. Cyanobacterial blooms contaminate freshwater reservoirs with increasing frequency due to nutrient pollution and warming water temperatures. Communities relying on affected water sources need rapid detection methods to implement protective measures. Deploying calibrated biosensors at water treatment facilities or