Highly Sensitive, Flexible, and Wearable Biosensor Platform for Advanced Precision Medicine
Overview
Biosensor based on nanomaterials have proven to exhibit high sensitivity which enables abrupt detection with low detection limit (LOD). Therefore, we use novel nanomaterials to create highly sensitive, flexible and wearable biosensors.
Non-Invasive Biosensors for Glucose Detection
Biosensors based on nanomaterials are becoming a crucial element for rapid point-of-care diagnosis. In this work, we test different nanomaterials for body vital signs monitoring such as glucose level, and for detection of different diseases. Novel fabrication processes are investigated along with biosensor sensitivity and accuracy. Our goal is to make affordable biosensors with high sensitivity for rapid testing. We demonstrate highly sensitive and conformal Indium Oxide nanoribbon Field-Effect-Transistor biosensors with a fully integrated on-chip gold side gate, which have been laminated onto various surfaces, such as artificial arms and watches, and have enabled glucose detection in various body fluids, such as sweat and saliva. The shadow-mask-fabricated devices show good electrical performance with gate voltage applied using a gold side gate electrode and through an aqueous electrolyte. The resulting transistors show a high on−off ratio and good mechanical robustness. With the electrodes functionalized with glucose oxidase, chitosan, and single-walled carbon nanotubes, the glucose sensors show a very wide detection range spanning at least 5 orders of magnitude and a detection limit down to 10 nM.
Highly Sensitive, Scalable, and Rapid SARS-CoV-2 Biosensor
Early diagnosis of SARSCoV-2 is crucial for controlling the global COVID-19 epidemic, which mandates a highly sensitive and scalable screening strategy. In this work, we report SARSCoV-2 biosensors based on Indium Oxide (In2O3) nanoribbon field-effect transistor (FET) devices and electronic enzyme-linked immunosorbent assay (E-ELISA). This E-ELISA applied phosphatase as enzyme, which has a much better stability than the widely used urease. These FETs were fabricated using a scalable and cost-efficient lithography-free process utilizing shadow masks. We demonstrate detection of SARSCoV-2 spike protein in both phosphate-buffered saline (PBS) buffer and universal transport medium (limit of detection [LoD]: 100 fg/mL). We also successfully detect spike protein specific antibody in both PBS and human whole blood (LoD: 1 pg/mL). Our biosensors display similar detection performance in different mediums, demonstrating that our electronic ELISA approach is not limited by Debye screening from salts and can selectively detect biomarkers in physiological fluids, indicating its capability for clinical diagnosis.