Field-based multiplex and quantitative assay platforms for diagnostics

Abstract

The U.S. military has a continued interest in the development of handheld, field-usable sensors and test kits for a variety of diagnostic applications, such as traumatic brain injury (TBI) and infectious diseases. Field-use presents unique challenges for biosensor design, both for the readout unit and for the biological assay platform. We have developed robust biosensor devices that offer ultra-high sensitivity and also meet field-use needs. The systems under development include a multiplexed quantitative lateral flow test strip for TBI diagnostics, a field test kit for the diagnosis of pathogens endemic to the Middle East, and a microfluidic assay platform with a label-free reader for performing complex biological automated assays in the field.

Effects of the Electrode Size and Modification Protocol on a Label-Free Electrochemical Biosensor

“…Currently, TBI diagnoses are made by tests such as magnetic resonance imaging (MRI), computed tomography (CT) scans, diffusion tensor imaging (DTI), or in-hospital observation. ,− However, these are expensive, impractical in resource-constrained environments, involve potentially harmful ionizing radiation, and require advanced expertise. ,, Studies have indicated that the cell death occurring after TBI results in the release of various brain proteins into biofluids. − The pattern and timing of post-TBI release for such protein biomarkers in biofluids can provide information of injury magnitude and outcome. Among various markers for TBI, glial fibrillary acidic protein (GFAP) is specific to brain tissue and released only after astrocyte death. − Papa et al have shown increased levels of GFAP protein in serum samples from human mild to moderate TBI patients. In their enzyme-linked immunosorbent assay (ELISA)-based study, they were able to detect GFAP in serum within 1 h of injury, with a lower limit of detection at 0.02 ng mL –1 .…”