Title: Magnetic and Electrochemical Preconcentration: a Route to Home-based, Picomolar Detection of a Heart Failure Biomarker
Abstract: The objective of the project described in this presentation is the creation of a new, low-cost, appropriately sensitive paper diagnostic devices for quantitative electrochemical detection of a heart failure marker known as NT-proBNP. The device is based on a metalloimmunoassay in which NT-proBNP (a short peptide) is sandwiched between two antibodies. One antibody is conjugated to a magnetic microbead and the other is linked to a silver nanoparticle. Upon formation of the sandwich, the complex is concentrated onto an electrode surface via a magnetic force induced by a magnet on the backside of the electrode. A series of electrochemical processes are then initiated that result in amplified detection by the silver nanoparticle label. This talk will describe the key iterations and improvements the sensor has undergone over the past several years, leading now to a device that detects NT-proBNP in serum throughout the risk stratification range for heart failure of 53 pM to 590 pM. The coefficient of variation of the assay is around 10% and the assay time is less than 10 minutes.