Quantum dot-linked immunoassay on a PMMA-based microfluidic device for biomarker detection

Immunoassay and biosensor development are burgeoning research fields with high translational impact potential due to the high demand for reliable biomarker detection. While needs are diverse and based on application, it is generally desirable to have an immunoassay that is rapid, robust, and easy to use. In order to meet those needs, our group has developed a quantum dot-linked immunoassay with a PMMA-based microfluidic substrate that is capable of detecting a variety of biomarkers. We developed a PMMA microfluidic using photlithography, electroplating, and hot embossing techniques. This novel technology uses an ELISA-like sandwich to capture biomarkers in an antibody - antigen - anti-antigen antibody complex. Specifically, we use a diamino poly(ethylene glycol), glutaraldehyde crosslinking combination to covalently immobilize primary antibody in combination with a quantum dot-streptavidin-biotin conjugated secondary antibody, which is quantified through an ultraviolet light emitting diode and charged-couple device camera setup. Our ultimate goal is to detect physiologically relevant biomarkers to better help physicians diagnose and treat their patients.