5^th Euro Biosensors & Bioelectronics Conference

Biography

Biography: James J Lai

Abstract

Clinical diagnostic tests such as immunoassay have been utilized for patient diagnosis to significantly improve health care and reduce costs by detecting trace amounts of certain proteins in patients for identifying harmful cells and troublesome cellular processes. The mainstream immunoassays utilize antibodies immobilized on solid supports for biomarker recognition and separation, which result in long assay time and compromise assay detection limit. In order to achieve higher assay sensitivity, our group has developed stimuli-responsive affinity reagents to address some of the biomarker separation challenges. The reagents such as antibodies conjugated with stimuli-responsive polymers respond sharply and reversibly to physical or chemical stimuli by changing their conformation and physical-chemical properties, i.e. 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, which provides opportunities to concentrate dilute biomarkers, thus improving detection ranges and expanding diagnostic options in immunoassays. In this presentation, I will discuss the utilities of stimuli-responsive affinity reagents for microfluidic immunoassay to enable sensitive detection for prostate specific antigen in human plasma as well as rapid biomarker purification and enrichment for infectious disease such as malaria.