An automated and mobile magnetoresistive biosensor system for early hepatocellular carcinoma diagnosis

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Most patients, however, are not diagnosed until advanced stage because early HCC lesions generally cause no overt symptoms, and the presence of cirrhosis adds another layer of complexity. While early diagnosis enables more therapeutic options and greatly improves survival rates, it is difficult to achieve. In order to detect early stage HCC, high-risk patients need to frequently measure serum biomarkers such as alpha-fetoprotein (AFP), and gold standards for detection involve less accessible and costly tests. In this work, we present an automated and mobile magnetoresistive biosensor system that allows quick, easy, and accurate detection of a panel of HCC related biomarkers. We first discuss the underlying principles of the giant magnetoresistive (GMR) biosensor system and its unique advantages in early detection of HCC. We also describe the development of hardware, software, and the bioassay, and demonstrate that it can perform an automated assay in 28 min, providing both qualitative and quantitative results. The user only needs to manually add sample into a disposable cartridge and press a button on the smartphone app, without the need for direct interaction with reagent liquids, or lab skills such as pipetting. With its portability, high sensitivity, and ease-of-use, the presented biosensor system has the potential to empower both medical practitioners and patients to achieve early HCC diagnosis. Furthermore, the GMR biosensor platform can be adapted to detect other protein or DNA biomarkers beyond HCC, bringing the goals of accessible mobile health even closer to reality.