A giant magnetoresistive reader platform for quantitative lateral flow immunoassays

•In this research, the quantitative lateral flow immunoassay (LFIA) reader platform utilizing the giant magnetoresistive (GMR) sensor was designed.•The permanent magnets standing diagonally opposite to each other magnetized magnetic label particles and bias the sensor simultaneously to maximize the quantification capability.•The system output changes due to the magnetic particle concentration change of 1 mmol/L was 0.67 μT.

Among quantitative lateral flow immunoassays (LFIAs) and assay readers, a system utilizing a magnetic field sensor for a reader and magnetic nanoparticle based-LFIA has recently been receiving a lot of attention because of its promising advantages such as high sensitivity and specificity. In this research, the quantitative LFIA reader platform utilizing the giant magnetoresistive (GMR) sensor was designed. The permanent magnets standing diagonally opposite to each other magnetized magnetic label particles and bias the sensor simultaneously to maximize the quantification capability. The performance of the reader prototype was evaluated with the imitative LFIA, which superparamagnetic nanoparticles were dispensed on the porous membrane. The system output changes due to the magnetic particle concentration change of 1 mmol/L was 0.67 μT, and 0.37 mV of sensor output decreasing was observed when the temperature increased 1 ° in Celsius.