Light-Based Sensor Detects Cancer Biomarkers in Blood at Sub-Attomolar Levels

Overview

• A peer-reviewed Optica study from Han Zhang’s team at Shenzhen University details an SHG nanosensor that integrates DNA nanostructures, quantum dots and CRISPR-Cas12a on a MoS2 surface.
• The device identified the lung cancer microRNA miR-21 directly in serum from patients, registering a clear signal with high sequence specificity.
• When Cas12a recognizes the target, it cleaves DNA tethers that position quantum dots above MoS2, producing a measurable drop in second-harmonic-generation output.
• The amplification-free design enables direct detection at ultra-low concentrations, which could shorten workflows, reduce costs and limit error-prone steps.
• Researchers plan to miniaturize the optical setup into a portable platform and program the sensor for additional biomarkers, pathogens and environmental toxins.