Lab-on-a-Chip Optical Immunosensor for Pathogen Detection

Abstract

This dissertation develops technology for microfluidic point-of-care (POC) immunoassay devices, divided into three papers, and explores the use of a quartz crystal microbalance for real time monitoring of blood coagulation in a fourth paper. The concept of POC testing has been well established around the world. With testing conveniently brought to the vicinity of the patient or testing site, results can be obtained in a much shorter time. There has been a global push in recent years to develop POC molecular diagnostics devices for resource-limited regions where well equipped centralized laboratories are not readily accessible. POC testing has applications in medical/veterinary diagnostics, environmental monitoring, as well as defense related testing. In the first paper, we demonstrated the use of latex immunoagglutination assays within a microfluidic chip to be an effective and sensitive method for detecting the bovine viral diarrhea virus. In the second paper the feasibility and general ease of integrating liquid core optical components onto a microfluidic lab-on-a-chip type device, for point-of-care AI diagnosis is demonstrated. In the third paper particle agglutination assays, utilizing light scattering measurements at a fixed angle from incident light delivery, for pathogen detection are explored in both Rayleigh and Mie scatter regimes through scatter intensity simulations and compared to experimental results. In the fourth paper a quartz crystal microbalance was used for real-time monitoring of fibrinogen cross-linking on three model biomaterial surfaces.