An Integrated Giant Magnetoresistance Microfluidic Immuno-sensor for Rapid Detection and Quantification of D-dimer

Abstract

A method for rapid detection and quantification of D-dimer as a biomarker of thrombosis was developed by utilizing giant magnetoresistance (GMR) sensor integrated with microfluidic technique and 100 nm magnetic particles (MPs) as signal probes. The MPs binding on the chip through specific immune reaction were measured by the GMR sensor and the concentration of D-dimer was obtained at the same time. The detection range of this method was from 5 ng mL−1 to 6500 ng mL−1, the detection limit was 5 ng mL−1, the intra relative standard deviation was less than 12% and the inter relative standard deviation was less than 14%. The whole analysis process could be completed within 9 min, and a good linear correlation between the results of GMR biosensor and Sysmex CA1500 was obtained. The method had the advantages such as high sensitivity, fast detection and good accuracy.