UW Bioengineering faculty James LaiStimuli-responsive Reagents for In Vitro Diagnostics

12:30 – 1:30 p.m., Foege N130 A (Wallace H. Coulter Seminar Room)

Talk abstract

Clinical assays can facilitate effective diagnosis to significantly improve patient care and reduce health care costs. For example, immunoassay, one type of clinical diagnostic tests, detect trace amounts of certain proteins in human plasma has enabled clinicians to identify harmful populations of cells and troublesome cellular processes and change management. The mainstream immunoassays utilize antibodies immobilized on solid supports for biomarker recognition and separation, which result in long assay time and compromise assay limit of detection. In order to enable highly sensitive clinical assays, our group has developed stimuli-responsive affinity reagents to address some of the biomarker separation challenges. In this presentation, I will discuss the utilities of stimuli-responsive affinity reagents for clinical diagnostics, including low-resource settings. The reagents such as antibodies conjugated with stimuli-responsive polymers respond sharply and reversibly to physical or chemical stimuli by changing from a hydrophilic state to a more hydrophobic state. Stimuli-responsive reagents can replace the antibodies immobilized at solid supports to overcome the mass transport limitations associated with heterogeneous immunoassays because the biomarker binding occurs in a homogeneous solution where molecular diffusion of the reagents facilitates rapid mass transport equilibration.The conjugates can interface with different diagnostic devices to enable rapid immunoassay by facilitating simple and effective biomarkers (or full sandwich immunocomplexes) separation and detection. Additionally, the rapid assay system is scalable to larger starting volumes (10x), which provides opportunities to concentrate dilute biomarkers, thus improving detection ranges and expanding diagnostic options in point-of-care immunoassays.


Dr. Lai received his B.S. in Chemical Engineering from University of Minnesota and Ph.D. in Chemical Engineering from Polytechnic Institute of New York University where he developed the magnetic nanoparticle synthesis using polymeric surfactants. He currently serves as a Research Assistant Professor in the Department of Bioengineering at the University of Washington. The focus of his research program is the development of molecular reagents for the applications in biomolecule separation and clinical diagnostic assays. The overall objective is to improve clinical assays’ sensitivity, specificity, throughput, and multiplexing capability. He has been developing new reagent systems that can interface with various analytical technologies to facilitate the corresponding diagnostic applications, including but not limited to infectious diseases. He has a strong interest in translating the group’s research and is a co-founder of the startup company, Nexgenia Inc., based on group’s diagnostic technologies.