UC San Diego

This research focused on using giant magnetoresistive (GMR) biosensors for point-of-caretesting to improve disease diagnosis and monitoring, thereby aiding healthcare decision-making. With their ability to detect subtle changes in local magnetic fields, GMR sensors offer a multiplexed and highly sensitive solution for various biomedical applications. By optimizing the surface chemistry for stable and reproducible conjugation of various biomolecules, the versatile platform enabled specific protein binding, including antibodies for Insulin-like Growth Factor Binding Protein-4 (IBP4) and Sex Hormone Binding Globulin (SHBG), as well as double-stranded DNA substrates for nuclease activity quantitation and protease substrates for quantitation of proteases such as papain and human neutrophil elastase. This work resulted in proof-of-concept of a sensitive, multiplexed, and point-of-care assay for predicting spontaneous preterm birth in pregnant mothers, critical as the complications posed by preterm birth (delivery before 37 weeks of pregnancy) are a leading cause of newborn morbidity and mortality. The assays were validated against mass spectrometry, showing high agreement. These assays have the potential to revolutionize prenatal care by providing timely and precise information to healthcare providers, ultimately improving outcomes for both mothers and infants. We expanded the capabilities of GMR sensors to multiplexed hydrolase quantification, including proteases and nucleases in biological samples. This development is vital for diseases marked by recurrent bacterial lung infections, such as chronic obstructive pulmonary disease and cystic fibrosis. This work highlights the transformative potential of GMR sensors in offering rapid and comprehensive insights into patients' health to enhance healthcare decision-making and improve patient outcomes.