HIGH SENSITIVITY PROTEIN DETECTION USING MICRO-MAGNETIC APTAMER PCR (MAP) TECHNOLOGY

Direct detection of protein biomarkers from complex mixtures over a wide range of concent rations is a significant challenge for clinical biosensor technology. In this work, we present Micro-magnetic Aptamer PCR (MAP) biosensor technology for specific, quantitative protein detection at pico-molar concentrations, directly from blood serum. The biosensor system integrates three complimentary technologies: a micro-magnetic separation chip to purify target proteins from complex mixtures, a DNA aptamer affinity reagent that binds to the target protein and interfaces with PCR amplification, and real-time PCR to quantitate protein concentrations. As a model system we demonstrate the detection of Platelet-Derived Growth Factor (PDGF), a cancer biomarker, in undiluted serum over four orders of magnitude from 1 nM to a detection limit of 124 + 6 fM.